512 SUMMARY OF CURRENT RESEARCHES RELATING TO 



the trocliopLore ; in other words, the anterior portion in front of the 

 pre-oral circlet of cilia retains its primitive relation to the axis of the 

 gastrula; this result, though arrived at by a different path, is 

 the same as that reached by Kleinenberg from his speculations on the 

 characters of the nervous system. 



Sternaspis scutata.* — F. Vejdovsky has some observations on 

 the work of other naturalists on this form, and takes the opportunity 

 of again expressing his conviction as to the intermediate position 

 oi Sternaspis (between Gephyrea and Chaetopoda). 



Monograph of the Chaetognatha.f — Dr. B. Grassi, in one of 

 the quarto publications of the Zoological Station at Naples, gives 

 a general account of the Chastognatha. The first j^art consists 

 of three chapters, the first of which contains a definition of the 

 group, and an account of its genera, Spadella and Sagitta, and its 

 20 real or nominal species. The geographical distribution is next 

 treated of; while the third chapter deals with the anatomy and histo- 

 logy. A bibliographical list of 65 papers precedes the second part, 

 which is devoted to " considerazioni." The Chsetognatha seem to form 

 a very distinct group of forms, with various resemblances to, but with 

 no less important differences from others, which have been supposed 

 to be their allies ; the fibrils of the muscular tissue present vari- 

 cosities which correspond with their dark stria3 ; the giant fibres 

 appear to be homogeneous ; the study of the peripheral nerve-plexuses 

 may throw some light on the physiological value of these plexuses in 

 other animals, while the changes undergone by the intestinal epithelium 

 during the process of digestion seem to support the view that the 

 secretion is the result of the action of the gland-cells. 



Direct Reproduction of Tsenia4 — P- Megnin has examined a 

 young dog, in the intestines of which he found 3 large examples of 

 TcBiiia serrata, and 12 small specimens. These last, only a few milli- 

 metres in length, must, the author thinks, have been derived by direct 

 reproduction from ova set free from the larger specimens ; they cannot 

 have been more than a few days old, and for a month the dog had 

 been under close observation, and had been fed on perfectly pure food. 

 Megnin has examples of similarly young forms taken from a human 

 subject, and he looks upon these cases of direct reproduction as afford- 

 ing an explanation of those pathological cases in w^hich Taenia-infection 

 has persisted for several years. 



Echinodermata. 



Democrinus parfaiti.§ — Mr. P. Herbert Carpenter points out that 

 this supposed new generic type || has been founded by Prof. Perrier, 

 owing to the erroneous descriptions of the basals of Bhizocrinua 

 lofotensis, which have been given by Sars and Ludwig, and his want of 



* SB. Bohm. Gesell, 1882, pp. 439-50 (1 pi.). 



t ' Fauna u. Flora des Golfes von Neapel. V. Die Chsetognathen.' 1883. 

 118 pp. (13 pis.). 



X Comptes Rendus, xcvi. (1883) pp. 1378-9. 



I Ann. and Mag. Nat. Hist., xi. (1883) pp. 334-6. 



II See this Journal, ante, p. 216. 



