654 SUMMARY OF CUEKENT RESEARCHES RELATING TO 



teristic nerve supply of the 5-ringed type. The third somite of the sub- 

 cesophageal ganglion has dorsally three rings, while ventrally there are 

 only two. The second somite of this group consists of two rings, the 

 anterior of which corresponds to three, and the posterior to two, annu- 

 lations. The first consists of a single ring, which is equal to five. 

 Details concerning other Hirudinea are given. 



Nematohelmintb.es. 



Filaria Bancrof ti.*— N. Taniguchi describes four cases of the occur- 

 ence of this parasite in Japan. He distinguishes two forms of larva, one 

 shorter and thicker than the other, enclosed in a loose transparent 

 envelope. The second has no envelope, and has a sharply pointed tail. 

 It is found within the body of the mother, in hydroccele fluid, in accumu- 

 lations of lymph, and in swollen lymph-glands, while the former type is 

 found only in the blood. Both types arise from the same female ; the 

 one in the blood is to be regarded as a modified form, which has under- 

 gone degenerative alteration due to the chemical and mechanical stimu- 

 lation of the circulation, and which ultimately dies, if not removed from 

 the host. 



Nematode associated with Decay in Plants.f— Haven Metcalf has- 

 studied Rhdbditis brevispina, or a closely related form which is commonly 

 and widely associated with decay in certain plants, such as Crocus, Petunia, 

 Colens, and Geranium. The nematodes seek wounded places on the 

 underground parts of these plants, probably in order to feed on the 

 plant juices. If they bear spores of pathogenic organisms they neces- 

 sarily inoculate the plants, and readily transfer the disease from plant to 

 plant. 



Structure of Filaria loa.J — A. Loos gives an account of the 

 minute structure of this nematode. He investigated a male and female 

 obtained from the human eye on the Gold Coast. The internal structure 

 has not hitherto been studied in any detail. 



Peculiar Structure of Epithelial Cells of Ovarian and Spermatic 

 Tubes of Ascarids.§ — L. Sala directs attention to the previously observed 

 fact that these elongated epithelial cells exhibit what appear as internal 

 fibres running parallel to one another. What he has discovered, by 

 using Heidenhain's iron-hsematoxylin, is that a definite filament extends 

 up the middle of each fibre, sometimes straight, sometimes zigzag. 

 These filaments are homogeneous and of uniform diameter. There is- 

 much probability that they represent an endocellular contractile 

 apparatus. 



Platyhelminthes . 



A Dioecious Cestode.|| — 0. Fuhrmann describes from the gut of 

 Podiceps domimcus, a remarkable cestode with separate sexes. A special 

 peculiarity is that it occurs in pairs, a male and a female, and for the 



* Centralbl. Bakt. Parasitenk., xxxv. (1904) pp. 492-500 (3 pis.). 



t TranB. Amer. Micr. Soc, xxiv. (1903) pp. 19-102 (1 pi.). 



X Zool. Jahrb., xx. (1904) pp. 549-74 (1 pi.). 



§ Rend. R. 1st. Lombardo, xxxvii. (1904) pp. 874-87 (1 pi.). 



|| Zool. Anzeig, xxvii. (1904) pp. 327-31. 



