178 SUMMARY OF CURRENT RESEARCHES RELATING TO 



e, Crustacea. 



Nucleolar Changes in Secretion of Hepato-Pancreatic Cells of 

 Hermit-Crab.* — L. Launoy describes in the mid-gut gland of Eupa- 

 gurus bemhardus the division of the nucleolus without subsequent 

 nuclear division ; the pulverisation of one or more of the nucleoli ; the 

 passage into the karyoplasm of inter-nucleolar granulations or the dis- 

 solution of these in the fundamental acidophilous substance of the 

 nucleolus — a process which he sums up in the term pyrenolysis. 



The phenomena of pyrenolysis, which are easy to follow in the 

 hermit-crab because of the size of the cells, precede or accompany the 

 appearance of the ergastoplasmic filaments. They therefore indicate 

 that the nucleolus plays a very active part in the elaboration of the 

 secretory granules. \ 



Function of Mid-Gut Gland of Crayfish, f — H. Jordan sums up 

 the results of experiments made by himself and others on the function 

 of the so-called " liver " of Astacus fluviatilis. It forms digestive juice 

 and absorbs food ; it does not differ very greatly from the short mid- 

 gut ; it is, in fact, a mid-gut greatly increased by evagination and pro- 

 tected from hard bodies. 



Two New Types of Epicaridse.J — J. Bonnier describes the external 

 characters of a single specimen of a new form, Cumoniscus kruppi 

 g. et sp. n., found by Lo Bianco in one of the Cumacea (apparently 

 a new genus of Leuconidse). A second new type, also represented by one 

 specimen, was found in a Schizopod described by G-. 0. Sars under the 

 name Gastrosaccus normani. From its resemblance to Dajus, Bonnier 

 calls thifl second novelty Prodajus lobiancoi. 



Marine Species of Hyalella. § — Ed. Chevreux describes a new 

 amphipod Hyalella richardi sp. n., a marine species of a genus hitherto 

 known only as represented by fresh-water forms from America. The 

 new form was obtained by MM. Bichard and Neuville on a cruise of the 

 Prince of Monaco's ' Princess Alice ' on the shore of the island of Alboran 

 (between Spain and the Mediterranean coast of Morocco). The genus 

 may be represented in the fresh waters of Morocco, but there seems no 

 doubt that the new species is marine. Chevreux gives a description of 

 both male and female forms. 



Crustacea and Pantopoda.|| — J. Meisenheimer gives a short account 

 of the development of Pantopoda or Pycnogonids (especially Ammothea 

 echinata) and discusses their systematic position. 



The cleavage and the differentiation of an inner and outer cell- 

 complex, the former including the elements of the mid-gut and of the 

 muscular-connective system, the latter forming ectodermic structures, 

 may be harmonised with similar phenomena in Branchipus, Moina, Ceto- 

 chilus, and Chondr acanthus. There is in all these a regular total 



* Comptes Rendus, cxxxvi. (1903) pp. 109-12. 



t Verh. Deutsch. Zool. Ges., xii. Vers. (1902) pp. 183-6. 



j Comptes Itendus, cxxxvi. (1903) pp. 102-3. 



§ Bull. Soc. Zool. France, xxvii. (1902) pp. 223-7 (2 figs.). 



|| Verh. Deutsch. Zool. Ges., xii. Vers. (1902) pp. 57-64. 



