ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 47 



5. Arachnida. 



Araneidan Fauna of Santa Cruz.* — Mr. W. J. Rainbow publishes 

 what seems to be the first systematic record of any branch of zoology 

 from this island (in the South Pacific). Twenty-four species are re- 

 corded, ten of which are new to science ; and it has been necessary to 

 create two new genera — Eunesiotes and Gnathopalystes. 



Functions of Mid-gut in Spiders and Scorpions.f — Sig. A. Berlese 

 concludes, from his investigations on this subject, that the epithelial cells 

 of the large glands, or hepatic caeca, have numerous functions, namely 

 the following : — (a) they absoib albuminoids, and retain them for a time 

 in coagulated form ; (b) they digest these substances into peptones ; 

 (c) they form uric excretions as the result of this fermentative work ; 

 {d) they pass these excretions into the lumen of the caecum, or retain 

 them ; (e) after the intracellular digestion the cells are detached, and 

 the contents are absorbed in the gland or in the colon ; (/) finally the 

 detached cells pass en masse into the colon, where they are broken up 

 into minute spherules, which lie in a substratum of very minute guanin 

 granules, derived from these cells or from those of the Malpighian tubes. 



The parenchyma, intercalated between the diverticula of the gland, 

 is probably the matrix of the epithelium ; and to its activity is due the 

 rich deposit of rounded uric calculi which are not got rid of. During 

 fasting the animal lives at the expense of the deposits of albuminoid sub- 

 stance in the cells of the intestinal gland, and these, during prolonged 

 fasting, disappear completely, and are replaced by uric calculi. The 

 excretions seem to consist of guanin, but some of the crystals inside the 

 cells suggest uric acid. 



Arachnoids from Pacific Islands.! — Herr E. Simon describes the 

 Arachnoids of Schauinsland's Expedition. They were collected at 

 Laysan, the Sandwich Islands, New Zealand, and the Chatham Islands. 

 The collection includes many new species. 



Completion of Monograph on Hydrachnids.§ — Dr. R. Piersig has 

 now completed his monograph on German Hydrachnids, instalments of 

 which we have briefly noticed from time to time. It deals with 30 

 genera, referred to 4 sub-families — Hygrobatinae, Hydryphantinae, 

 Eylainae, and Hydrachninae — and is a monumental piece of work de- 

 voted to an interesting family which has found comparatively few 

 students in this country, though we are glad to see that the observations 

 of C. J. George and C. D. Soar figure prominently in the bibliography. 



New Hydrachnids. |] — Herr Karl Thon describes a number of new 

 species from Bohemian ponds belonging to the genera Hydrachna and 

 Arrenurus. 



* Proc. Linn. Soc. N.S. Wales, xxiv. (1899) pp. 304-21 (2 pis.), 

 t Kiv. Patol. Veg., vii. (1898, received 1899) pp. 226-51 (3 pis.). 

 % Zool. Jahrb. (Abt. Syst.), xii. (1899) pp. 411-37. 



§ Bibliotheca Zoologica (Leuckart and Chun), Heft 22 (1897-1900) 601 pp. 

 (51 pis.). 



|| Zool. Anzeig., xxii. (1899) pp. 496-9 (3 figs.). 



