ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 759 



Nematohelminth.es. 



New Nematode.* — J. Xoordhoek Hegt describes Chi amy don emu 

 t'elineinn g. et sp. n. from the stomach of cats in Batavia. It appears to 

 occupy a somewhat isolated position, as H. F. Nierstrasz f indicates. 

 The onter layers of the cuticular form in the posterior half of the body 

 a sort of mantle within which the female can retract itself. In the 

 male this " mantle " ends at the base of a broad caudal portion with four 

 paired ridges, seventeen sensory papillae, and numerous cuticular promin- 

 ences. The head has three unstalked sensory papilUe and two lips, each 

 with three teeth. The posterior end in the female is pointed. In the 

 male there are two unequal spines and three large pear-shaped glandular 

 organs opening into the cloaca. The lateral areas are strongly folded. 

 The pharynx has a bulb. The colour is whitish-red. The animal is 

 ccelomyarian and polymyarian. 



Structure of Filaria bancrofti.J— S. Hida has made a fresh study of 

 this Nematode. The adult female is 80-100 mm. long, by 1 ■ 8-2 ■ 5 mm. 

 broad, and is whitish in colour. In both sexes the head-end is thickened 

 in a club-like manner, and the oral aperture is terminal. The genital 

 aperture is funnel-shaped ; between it and the uterine sac there is a 

 spiral canal with three coils. In the uterine sac there are embryos 

 towards the efferent portion, and ova at the other end. The sac is 

 simple to begin with, but it becomes divided into two by a partition. 

 The anus is lateral near the end of the tail. 



The male is 30-45 mm. in length, and thinner than the female. Its 

 genital canal is a simple sac, containing spermatozoa and other cellular 

 elements. It opens with the gut into a cloaca just above the end of the 

 tail. From the cloaca two spicules are protruded, which serve to grip 

 the female in the sexual union. 



Compression Experiments with the Fertilized Ovum of Ascaris 

 megalocephala.§ — S. S. Girgolaff finds that the abnormal arrangement 

 of blastomeres produced by compression may induce abnormalities in the 

 embryo. This must result when the developing egg cannot re-arrange 

 the cells after the compression is removed. The arrangement of the 

 blastomeres in one plane results in a thickening of this or that portion 

 of the embryo. There is an observable struggle between the regulative 

 tendency and the direct influence of the pressure. The results of the 

 compression vary considerably according to its degree ; it may prevent 

 the egg from dividing at all. It inhibits the development and lowers 

 vitality. The author gives an account of the various results which he 

 has observed, and notes that the division under compression and the 

 division under centrifuging influence have some features in common. 



Role of Plastochondria in Fertilization of Ascaris megalo- 

 cephala.|| — Fr. Meves finds that formed elements — plastosomes or plasto- 

 chondria— pass from the spermatozoon into the ovum, where they meet 



* Tijdschrift Nederland. Dierk. Ver., xii. (1910) pp. 5-44 (1 pi.). 



t Tijdschrift Nederland. Dierk. Ver., xii. (1910) pp. 45-59. 



X Centralbl. Bakt. Parasitenk., lte Abt., lx. (1911) pp. 133-41 (9 figs.). 



§ Arch. Mikr. Anat., lxxvi. (1911) pp. 770-96 (30 figs.). 



U Arch. Mikr. Anat., lxxvi. (1911) pp. 683-713 (3 pis.). 



