| Earthworm is a collectable name of the Oligochaeta, the Annelida in terrestrial species. Lumbric, the famous French pioneer of evolution was the first one who opened the terrestrial Oligochaetes study and established annelids. Templeton established Megascolex in 1844. Kinberg established Pheretima derived from Pheretima californica and Pheretima Montana. In view of the current classification of terrestrial earthworms have different academic point of view. In this paper, we introduced the classification system according to the method established by older generation of scholar Yi Chen.Megascolecidae is the biggest one of Earthworm, and the Pheretima is the biggest genus in Megascolecidae. Pheretima distributed in worldwide, and 31 species and subspecies of them were found in our country whereby distributed in different province such as Hebei, Gansu, Tibet, Sichuan, Yunan, Hubei, Anhui, Jiangsu, Zhejiang, Jiangxi, Hunan, Hainan, Taiwan, Hong Kong and so on. Pheretima can be used as medicine in variety and it’s a source of animal of Chinese medicine-pheretima, and are widely used in agricultural production, medicine, ecology, treatment of organic waste, reconstruction of soil and food. Pheretima schmardae belongs to Annelida, Oligonucleotides, Oligochaeta opisthopora, Megascolecidae, Pheretima.The earthworm widely distributes in the world, except desert and snow ice-covered area or non-soil and non-plant area, it almost distributes in any area of the world. From ancient to today, the relationship between earthworms and human is getting more and more closely. Out of these terms it was found that the function of earthworm exerts an important influence on the human life, and their contributions are recognized all over the world. As early as seventeenth century, a series studies on earthworms were started. With the development of science and technology, the demand of earthworm application and the related research is being more deeply, mainly on:the biological basic theory, earthworm application, the development and utilization of earthworm etc. Great achievements have been made in seventeen and eighth century. The investigation focused on earthworm morphology of organ, but basic drawing of the map. These work mostly drawn a description by foreign taxonomists. The research of the organization level is almost blank. The study of Chinese terrestrial earthworm taxonomy was about a century delayed than earthworm taxonomy study of the world. The first described terrestrial earthworm Pheretima aspergillum (Perrier,1872) in China is collected by Perrier from Xiamen, Fujian. From then on, began the classification study of terrestrial earthworm. In the early period of the Republic of China, Yi Chen, Bingwen Fang, represented the Chinese experts, they have investigated the base taxonomists mainly launched the classification. Except the Chinese earthworm, significant progress has been made in earthworm research and established a foundation.The current situation:there are very few of scholars work in the research of earthworm taxonomy and it’s a lot of work to be carried out in researching on the classification of Chinese earthworm. At present, the index of the classification and identification for earthworm still use the method by older generation of scholars. The DNA bar coding technology has been applied to the classification of earthworm, but it still needs time to be examined. At present, many problems in the classification and identification of earthworm had to be deal with, since it was lack of systematic morphological studies on it. So, it’s very necessary to study the morphology of earthworm.The histological research is an important part of the study of morphology, but the current research on earthworm tissue is almost blank, and lack of systematic and complete histological atlas, moreover, it hasn’t seen color atlas. The digestion and reproduction is the most directly relevant to the farmed earthworm. At the same time, the morphology of reproductive system is the important basis for classification and identification. the morphology of digestion system is the important basis for earthworm to deal with the environment rubbish. Therefore, in this study, we focused on the morphology of the reproductive system and digestive system. In addition to fill gaps in the histological study, also provide reference for related research.In this paper, we focused on the morphology of the reproductive system and digestive system using the Ph. schmardae as material by general observation, tissue slice, H.E staining and scanning electron microscope.The main conclusions of this study are:1) Some of the spermatheca holes of different sex mature individuals did have accessory gland, but some of them did not. Accessory gland is a protrusion wherein the gland cells and columnar epithelial cells gradually fusing near epidermal cell. Spermathecal pores showed a protrusion with an opened hole on the top, linked to the end of the blind pipe. The cuticle on the open hole is thicker than that in surroundings. Mussels at the blind pipe developed well and the inner wall covered with columnar epithelial cells. Ampulla showed bumpy surface, with different size and shape since the amount of fluid in Ampulla diverse. Also, there are a large number of vascular cells lining the inner surface of the altar capsule; the inner cells are secretary cells, and the nucleus locate near the basal membrane, also they continuously secreted nutrients at the sexual maturity stage. The blind pipe alters in different individuals; the inner wall demonstrates a fold structure, composed of columnar epithelial cells, the nucleus locates near the basal membrane. The sperm in blind tube clump in messy and there are a small amount of vegetative cells around sperm cells; The nucleic acid content of inner cells lining spermatheca is abundant and they also secret protein substances. The arrangement of sperm in bind tube as follow:more ordered sperm distribute in the bottom, the top is very orderly, the head and the tail of the sperm are arranged orderly cross, the head direct to the wall, and the tail to the sac center.2) The seminal funnel wall contained a large amount of muscle fiber which surface is ciliated. The head of the sperm regularly arranged along the direction of cilia distribution, and the tail turns inward. Seminal vesicle is composed with small and big parts, the number of sperm is less in top pouches, but there is a large number of sperm within the big sac, and aggregate in protein material as small pile. The testis sacs are connected with the vas deferens through the funnel. The vas deferens has the function of sperm transport which have cubic epithelium inner wall.3) The internal of male genital pore is plicate. Under the special condition, the penises are out of the male genital pore and the length is different. The prostate tube wall is consist with strong circular muscle, and there are two parallel, isometrical tubes, suggested the tube transport sperm and prostatic secretion.4) The genital pore shape in the clitellum indicated that the epidermal cells are glandular. The oviducts joined together in the body wall under the abdominal nerve, and the inner surface distribute with cilia to transport egg. Ovaries were scattering distributed, and the gradual development of the ovum from base of ovary outwards can be observed.5) The sperm is composed of head and tail, the head contents high nucleic acid, and the tail is slender. the Kaumas-Coomassie brilliant blue staining method is better than H.E staining, and scanning electron microscope was also important to observe the morphology of sperm.6) In the digestive system, the inner surface of digestive tube before gizzard cavity masks with epithelial cells, and have not cilia. The gizzard has powerful circular muscle that may closely related to physical digestion, and the epithelial cells of inner surface with compact structure, and also there is no cilia. In the surface of the digestive tube (including intestinal caeca) after gizzard distributed with microvilli which correlated with the absorption of nutrients. The anal is slip-shaped, the epithelium tissue of inner cavity surface thickened, and there are large number of muscle cells in the wall.In summary, the results of this study systemically demonstrated the morphology and structure of the reproductive system and digestive system of the Pheretima schmardae in detail, and fulfilled some blanks in earthworm morphology study, which may provide reference for the related research. In this study it’s observed:1) genital system:the polymorphism of male genital pore tips have been observed, suggesting that it needs more careful to consider the polymorphism of male genital pore tips in the classification and identification of earthworm; The storage seminal vesicle consists of two parts, and the maturation and storage site of sperm are partition, and s higher evolution; the fibrous columnar epithelium plays an important role in the transportation of sperm.2) digestive system:gizzard Is the main physical digestive organ; Intestinal and blind in both have columnar epithelial cells and blood distribution suggest that:intestinal and blind are the major site of absorption of nutrients, and enter the blood circulation. |
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