232 Miscellaneous. 



All deptlis of the lake have furnished (jraninuirida\ The greatest 

 depth to which tlie author has hitherto carried his dredgings, namelv 

 1373 metres, proved to bo as well peopled as the littoral zone, 

 although the number of species was less tluin at higher levels. 

 However, this comparative ])overty seems to be attributable to tho 

 fact that the exploration of great depths is attended with great dif- 

 ticulties. Dr. Dybowsky has no doubt that more regular investiga- 

 tions carried on between 500 and 1300 metres would be rccompcDsed 

 by the discovery of new species. 



Most of the (Jammaridicof Lake Baikal which live at small dej>th3 

 are vividly coloured ; but with the increase of depth the coloration 

 gradually diminishes, and tlie species living below 700 metres arc 

 more or less whitish in tint. Some varieties, coming from greater 

 depths than those inliabited by the specific tyi>e, are distinguished by 

 the ])aleness of tlu'ir bodies and eyes, and also, in some cases, by the 

 more elongated and slender form of their locomotive appendages. — 

 Horte Soc. Ent. Ross. Bd. x. Supplement ; Bibl. Univ., Bull. Sci. 

 1874, p. 372. 



On the Mode in which Amoeba swallows its Food. 

 By Prof. J. Lkidt. 



The author remarked that he had supposed that Amceha swallows 

 food by this becoming adherent to the body and then enveloped, 

 much as insects become caught and involved in syrup or other 

 viscid substances. He had repeatedly observed a large Amoeba, 

 which he supposes to be A. iwinceps, creep into the iuterstices of a 

 mass of mud and appear on the other side without a particle ad- 

 herent. On one occasion he had accidentally noticed an Amceha 

 with an active flagellate infusorium, a Urocentnun, included between 

 two of its finger-like pseudopods. It so happened that the ends of 

 these were in contact with a confervous filament ; and the glasses 

 above and below, between which the Amaha was examined, efiec- 

 tuallj- prevented the Urocentmm from escaping. The condition of 

 imprisonment of the latter was so peculiar that he was led to watch 

 it. The ends of the two pseudopods of the Amaha gradually ap- 

 proached, came into contact, and then actually became fused — a 

 thing which he had never before observed with the pseudopods of 

 an Amoeba. The Urocentnun continued to move actively back and 

 forth, endeavouring to escape. At the next moment a delicate film 

 of the cctosarc proceeded from the body of the Am<yba, above and 

 below, and gradually extended outwardly so as to convert the circle 

 of the pseudopods into a complete sac, enclosing the Urocentrum. 

 Another of these creatures was noticed within the Amceha, which 

 appeared to have been enclosed in the same manner. 



This observation would make it appear that the food of the 

 Amrgha ordinarily does not simply adhere to the body, and then 

 sink into its substance, but rather, after becoming adherent to or 

 covered by the pseudopods or body, is then enclosed by the active 

 extension of a film of ectosarc around it. — Proc. Acarl. Nat. Sci, 

 Philad. p. 143. 



