G18 SUMMARY OF CURRENT RESEARCHES RELATING TO 



work, which being a Government publication is limited in its dis- 

 tribution. The synopsis will serve to lead the observer directly to 

 the proper genus and species with a fair degree of certainty, and the 

 index is arranged as a check-list, so that a record may be kept of the 

 species found. 



The book will undoubtedly be very useful to microscopists, and 

 we should be glad to see the same plan adopted with the Infusoria 

 and Diatoms. 



Rhizopods as Food for Young Fishes.* — Mr. S. A. Forbes has 

 found that the young of some of the "Suckers" (Catastomidae) have 

 the intestines full of the tests of Difflugia and Arcella. Professor J. 

 Leidy examined two slides of intestinal contents, and recognized four 

 species of the former genus and two of the latter with an unknown 

 Ehizopod shell in form resembling that of Arcella discoides. He 

 considers it an interesting discovery that the young " Suckers " 

 should use the Ehizopod shells to obtain as nutriment their little 

 stores of delicate protoplasm. 



Rhizopods in Mosses.j — Professor J. Leidy records the finding of 

 seventeen species of Ehizopods among the water squeezed from mosses 

 (Hypnum and Sphagnum) on the top of Eoan Mountain, N. Carolina, 

 at an altitude of 6367 feet. 



Fission of Euglypha alveolata.J— Dr. August Gruber states that 

 in well-developed examples of this Protozoon we can detect in or on 

 the superficial layer, and at the point where the nucleus is placed, a 

 number of small corpuscles distinguished by their high refractive 

 power. These are the so-called shell-plates, the presence of which 

 has been noted by various observers. When the Eughjpha is about to 

 divide, protoplasm escapes from the orifice, and, at about the same 

 time, these concavo-convex plates begin to move and pass towards the 

 orifice ; at first they lie irregularly in the sarcode. After a short 

 time about eighty shell-plates will have passed from the parent- 

 animal and formed a kind of fir-cone around the extended protoplasm. 

 Soon the new Euglypha resembles its parent, and, during the forma- 

 tion of the new shell, fine granular or coiled lines will have ap- 

 peared in the nucleus. An essential difference is, however, to be 

 found in the absence at first of any nucleus in the daughter- 

 individuals, which in time come to them from the parent. While the 

 new shell is being formed changes are set up in the nucleus by the 

 appearance in it of fine granules or coiled lines ; the nucleus soon 

 alters its form, exhibits a longitudinal striation, the first sign of its 

 future division, and becomes so long as to almost equal the whole 

 length of the parent-animal. It then becomes divided in the middle, 

 and one half passes into the newly formed individual. The author 

 then gives an account of the rotation of protoplasm. § 



The chief results of the careful comparison between this and other 



* Proc. Acad. Nat. Sci. Phila., 1881, pp. 9-10. 



t Ibid., 1880, pp. 333-40. 



X Zeitscbr. f. wiss. Zool., xxxv. (1881) pp. 431-40 (1 pi.). 



§ See this Journal, ante, p. 69. 



