362 .iM\i;V OF CURRENT RESEARCHES RELATING TO 



lanceolatum. Ee round cercarise in the liver of a badly infected sheep. 

 They are very minute, only 570 ft in length, of which the tail forms 

 '2bQ fx. They showed no oral differentiations and no skin-glands. From 

 the absence of glands, as well as from the persisteni tail, the author 

 infers that the cyst stage, on grass or the like, has been wholly suppressed, 

 and that the cercariae are taken into the sheep with the wafer. The 

 intermediate host is probably a snail. Zarnik also refers to the develop- 

 ment of the gonads, and notes that the ovary is always ripe before the 

 testes. 



Stilesia and its Relatives.* — L. II. Gough gives an account of the 

 tapeworms of the sub-family Avitellina;, which includes Stilesia and a 

 new genus Avitellina. He also describes the minute structure of 

 Avitellina centripunctata (Riv.). The name Avitellina denotes the 

 absence of a vitelline gland, and it may be noted that in Avitellina the 

 uterus is single, there is a single paruterine organ, the testicles are in 

 four groups, the genital canals pass dorsally of the dorsal canal, whereas 

 in Stilesia the uterus is double, there are two paruterine organs, the 

 testicles are in two groups, and the genital canals pass ventrally of the 

 dorsal canal. 



Incertae Sedis. 



Irish Polyzoa.f — A. R. Nichols reports on a collection of Polyzoa. 

 mostly Cheilostomata, made off the Irish coasts. It consists of 101 

 species, 80 of which were obtained off the west coast at a greater depth 

 than 50 fathoms. Twenty-three species are recorded for the first time 

 from the Irish coast, and six of these, Filisparsa irregularis, Menipea 

 smittii, Scrupocellaria intermedia, Kinetoskias smittii, Hemicyclopora 

 maltispinata, Pasythea ebumea, do not appear to have been previously 

 obtained on any part of the British coasts. On some fragments of a 

 species of Brettia, probably a new variety of B. pellucida Dyster, ooecia 

 were found for the first time for this genus. 



Rotifera. 



Histology of Rotifera. ! — Gustav Hirschfelder contributes a detailed 

 account of the histology of various organs of Eosphora, Hydatina, Euch- 

 lanis, and Notommata. The organs of which the finer structure is more 

 particularly described are the following : — the rotatory organ and cilia ; 

 central nervous system and peripheral nerves ; sense-organs ; retro- 

 cerebral apparatus and subcerebral gland ; eye ; digestive tract ; mastax 

 and jaws ; and the muscles. The clear account of the retrocerebral sac 

 and subcerebral gland, overlying the brain, with their respective forked 

 frontal ducts, is a substantial advance in the understanding of these two 

 organs, which formerly were confounded with the brain. The use of the 

 secretion of these two glands still remains a mystery. The description 

 of the jaws of Eosphora digitata and their mode of action is most instruc- 

 tive, and reveals a wonderfully ingenious and delicate apparatus confined 

 within the very small space of the mastax. 



* Quart. Journ. Micr. Sci., lvi. (1911) pp. 317-85 (3 pis. and 6 figs.). 



t Scient. Invest. Fisheries Ireland, i. (1910, published 1911) pp. 1-37 (1 pi.). 



\ Zcitschr. wiss. Zool., xcvi. (1910) pp. 209-35 (5 pis.). 



