188 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Ceregonus are found, there also will be found the large deep-water 

 Cladocera, such as Holopedium and Bythotrephes, which serve these 

 fish as food. 



The Entoniscida.* — Prof. E. Kossmann finds that only five previous 

 papers by three investigators (F. Miiller, Fraisse, and Giard) form 

 the bibliography of this group. European forms are said to be 

 hermaphrodite, while the Brazilian appear to be dioecious, but the 

 author has found the males of the former, though their relatively 

 smaller size is obviously a difiiculty which may have caused the 

 earlier incorrect statement. Two genera — Entoniscus and Entione — 

 are recognized, and the differences between their males pointed out. 

 In their case, as in that of the females, the peculiarities of the group, 

 and their common chai acters with the Bopyridse are insisted on ; the 

 differences between the females of the two genera of Entoniscida are 

 duly noted, and the views of earlier naturalists critically examined. 

 The author does not think it probable that there is any change of 

 host, as Fraisse has supposed. 



It is pointed out that two larval forms obtain with E. cavolinii ; 

 some of the differences which previous investigators have detected 

 and looked upon as specific, he believes to be due to differences in 

 age, and the tegumentary glands discovered by Fraisse have not been 

 made out by Kossmann. 



The Bopyridse.t — In this third contribution to a knowledge of 

 these forms. Prof. R. Kossmann deals with lone thoracica and Cepon 

 portuni n. sp. (found in Portuniis arcuatus), of which he gives a careful 

 account, with especial reference to the gills, and the differences 

 between the male and female. So rare are these forms, that 10,000 

 Brachyura were in vain opened by Salvatore Lo Bianco, of the Naples 

 Zoological Station, before it could be said that a Bopyrid was to be 

 found in any European Crustacean. The parasitism of this creature 

 is neither common nor rare, but only gives rise to local epidemics. 



Vermes. 



Anatomy and Histology of Scoloplos armiger.J — W. Mau has 

 selected this common form for a study of the Polychaetous Annelids. 

 The methods of examination have comprised the investigation of 

 living forms, and of specimens hardened by being killed in picric or 

 chromic acids, in which they were left for a fortnight ; after washing, 

 they were placed first in dilute and then in absolute alcohol ; other 

 specimens were killed in dilute, then placed for some time in stronger, 

 and, finally, in absolute alcohol. The examples best adapted for 

 sections were found to be those that had been treated with chromic 

 acid. The most suitable colouring matters were saffranin, alum- 

 cochineal, and picro-carmine. Sections were cut by the microtome 

 or the razor after imbedding in paraffin. 



* MT. Zool. Stat. Neapel, iii. (1881) pp. 149-69 (2 pis.). 

 , t Ibid., pp. 170-83 (2 pis), 

 j Zeitsclir. f. wiss. Zool., xxxvi. (1881) pp. 389-432 (2 pis.). 



