388 SUMMARY OF CURRENT RESEARCHES RELATING TO 



differentiated, and are to be referred for a cause to the creeping mode 

 of life of these worms ; some of these marginal tentacles have the 

 form of a fold, and are indeed nothing more than permanent folds of 

 the anterior margin of the body in which the primitive (and in 

 Anonymus the persistent) sensory organs were more numerously 

 aggregated. From these folded tentacles the pointed ones appear to 

 have been derived. Auditory organs have been found only in Lepto- 

 jplana otopliora. In addition to the special organs, it is to be noted that 

 the whole surface of the Poly clad body is extremely sensitive. 



In the tenth chapter the author commences, but does not complete 

 his account of the generative organs, a notice of which must therefore 

 be postponed till the second part of this important work is published. 



Early Stages in the Development of Balanoglossns.* — W. Bate- 

 son describes with great minuteness the early stages in the develop- 

 ment of an undetermined species of Balanoglossus, up to the formation 

 of the layers and the commencement of the nervous system. Especial 

 stress is laid on the points of difference between this larva and 

 Tornaria. The Balanoglossus larva is opaque, has no preoral or longi- 

 tudinal postoral bands of cilia, water-vascular system, eye-spots, or 

 contractile string, thereby differing remarkably from Tornaria, which it 

 resembles on the other hand in the possession of a transverse band of 

 cilia and an apical tuft of cilia. A striking similarity is observed to 

 exist between the general history of the early development of this larva, 

 and that described by Hatschek for AmpMoxus, this resemblance being 

 more particularly strong in the situation and mode of origin of the 

 central nervous system and of the mesoblastic somites. 



"New Rotatoria.t — Dr. E. v. Daday, after devoting several years 

 to the study of the Hungarian Eotifera, especially those of Tran- 

 sylvania, in 1882 visited the groups of pools in the Mezosey, and 

 found in the Mezo-Zaher pool several new species, one of them 

 representing a new genus. 



Brachionus Margoi n. sp. most nearly approaches B. amphiceros, 

 especially as regards the processes of its carapace ; but in that species 

 the processes are all of equal lengths, while they differ in length in 

 the new one. The essential distinction between the two species is to 

 be sought in the rotatory organ, the musculature, the jaws, and 

 salivary glands. 



ScMzocerca n. gen. S. diversicornis n. sp. resembles Brachionus in 

 internal organization, but differs so much from the Brachionea, and, 

 indeed, from all Eotatoria, in the structure of its foot, that the author 

 regards it as the type of a new genus. 



Asplanchna trioplithalma n. sp. is one of the largest of the Eoti- 

 fera, and very similar to A. Sieholdii {Notommata Sieholdii Leyd.) 

 in the form of the body, the digestive apparatus, and the ovary. But 

 the nervous system, the aquiferous vessels, and the construction of the 

 rotatory organ show such considerable differences that the author has 

 no hesitation about separating the two species, and he gives the new 



* Quart. Journ. Micr. Sci., xxiv. (1884) pp. 208-36 (4 pis.), 

 t Math. Naturwiss. Ber. aus Ungarn, i. p. 261. See Add. and Mag. Nat. 

 Hist., xiii. (1884) pp. 309-10. 



