ZOOLOGY AND BOTANY, MICROSCOPY, ETC. ( t9 



careful diagnosis (and a useful key) of nine species of Allocreadium — 

 Distomid parasites of marine fishes. 



New Trematoda from the Labridge.* — Dr. A. Looss describes various 

 new flukes from these fisb, the most striking being a form which, 

 together with Olsson's Distommn viviparum, be places in a new genus as 

 Zoogonus minis g. et sp. n. As indicated in the name, the most strik- 

 ing character is the viviparous habit, the egg-shell being absent, and 

 the young developing free in the uterus as ciliated miracidia of large 

 size (length 0*13 mm.). These at one stage of development are en- 

 veloped in a cellular investment, similar to that found beneath the shell 

 in other Trematode embryos. This is lost at a later stage, and the 

 miracidia become naked. 



Avian Trematoda. f — M. Braun publishes a revision of the flukes 

 found in Birds. Twenty-four sjiecies of Distomum are discussed, syno- 

 nyms, type species, hosts, and specific characters being all given. The 

 second part of the paper contains descriptions of a number of new 

 species, found by the author chiefly in birds from Brazil. 



New Tape-worm in Man.J — Dr. 0. von Linstow describes Tsenia 

 asiatica sp. n., from Aschabad in Asiatic Russia. In the structure of 

 its uterus and other genital organs the new form belongs to the Davainea 

 type ; it is certainly distinct from any of the (8) species of Tsenia 

 hitherto recorded in man. 



Bothriocephalus histiophorus sp. n. § — A. E. Shipley describes 

 under this name a tape-worm obtained from the intestine of the sword- 

 fish, Histiophonis sp. The scolex is unarmed, and there is no neck. It 

 would appear that the eggs leave the ripe proglottides within the body 

 of the host, and do not remain within these until they break off. There 

 is no receptaculum seminis, and the uterine pore is not median as in 

 most species of the genus. 



Position of Nerve-cord in Abothrium reetangulum. || — Dr. Al. 

 Mrazek figures and describes sections of this tape-worm to show the 

 position of the longitudinal nerve-ends. He finds that their relation to 

 the genital organs is very variable, for they are sometimes dorsal to the 

 cirrus-sac and vagina, and sometimes ventral. An interesting case is 

 shown in a proglottis with double genitalia, for here the longitudinal 

 nerve at one side is dorsal and at the other ventral to the organs. 



Development in Cestoda.^T — G. Saint-Remy has studied the early 

 development in two tape-worms of the horse, Anoploccphala plica ta and 

 A. marnmillana, in which the developmental processes prove to be 

 similar in all essentials. In the young eggs the proportionately small 

 egg-cell lies at the side of the yolk-mass. Later, this yolk -mass divides 

 into two parts and becomes gradually absorbed, while the egg-cell gives 

 rise to three sets of cells, or rather to three sets of nuclei, for cell- 



* Centralbl. Bakt., 1" Abt., xxix. (1901) pp. 39S-405, 437-42 (C figs.). 



t Tom. cit., pp 560-8, 941-8. X Tom. cit.. pp. 982-5 (5 figs.). 



§ Proc. Camb. Phil. Soc., xi. (1901) pp. 209-13 (1 pi.). 



f|i Centralbl. Bakt., l ,e Abt.. xxix. (1901) pp. 569-71 (3 figs.). 



«[[' Arch. Parasitol . iii (1900.) pp. 292-315 (1 pi.). See also torn, cit., pp. 739-40. 



