ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 225 



then immersed in the water. The outbreak of war put an abrupt end 

 to the work, and many of the mice died at sea too soon to show any 

 result. One mouse, however, infected at Aden from the remaining 

 living molluscs, was safely brought to London. Live male and female 

 schistosomes in copula were found in the portal veins, and a permanent 

 preparation was made. The results confirned those of Miyairi, who had 

 shown earlier (in an inaccessible Japanese paper) for S. japonicuni that 

 one or more species of water-snail act as intermediate host of the parasite. 

 To the paper is appended a description, by G. C. Robson, of the snail 

 used in the experiment. Though very abundant in some localities, it is 

 apparently a hitherto undescribed species. 



^ Structure of a New Tapeworm.* — T. Harvey Johnston gives an 

 account of Ophiotsenia longmani sp. n., from a Queensland python 

 {Aspidiotes ramsayi). He describes the very thin cuticle, the cortical 

 calcareous bodies, the strong anterior muscles, and so on. The author 

 also reports from a coypu the bladderworm Ccennrus serialis. or, better, 

 Multiceps serialis, not uncommon in rabbits. Tiny cestodes of the genus 

 Nematotsenia were got from New South Wales frogs, and some other 

 parasites are recorded. 



Incertae Sedis. 



Sex in Dinophilus.t — Paul de Beauchamp finds that the large 

 ■opaque ova of this aberrant type may sometimes develop into males. 

 These are abnormal, but they produce spermatozoa. It has hitherto 

 been believed that the large ova gave rise to females only, and that 

 the small transparent ova gave rise to all the males. It can no longer 

 be said that the sex of Dinophilus is absolutely dependent on the size of 

 the ovum and the relative amount of yolk which is usually (not always) 

 correlative with the size. 



Echinoderma. 



Development of Asteroids. :f— J. F. G-emmill deals first with Asterias 

 glacialis. A small solid outgrowth from the stomach-wall is found in 

 nearly all the early larvse, and a brood occurred in which this outgrowth 

 was larger, developed a central cavity, and fused with the backward- 

 growing coelomic cavity of the left side. It is interpreted as a rudi- 

 mentary posterior enterocoelic outgrowth. In Crihella oculaia it is 

 shown that the perihtemal pouch belonging to the madreporic inter- 

 radius arises from the dorsal horn of the left posterior coelom ; that 

 the aboral skeleton arises in the form of scattered plates without 

 definite radial and interradial arrangement ; and that the terminals are 

 formed by fusion of several of these plates. 



The author's previous description of Solaster endeca is supplemented 

 in various points : all the perihasmal pouches arise from the posterior 



* Mem. Queensland Museum, v. (1916) pp. 186-96 (16 figs.), 

 t Comptes Rendus, clxiv. (1917) pp. 56-8. 

 " " ' 1916, pp. 553-65 (2 pis.). 



