ZOOLOGY AND BOTANY, MICROSCOPY, ETC. f)! 



derived from monoiuiclear cells, generally large lymphocytes. The 

 gramilations, at first amphophiloiis, are transformed into acidoiihilous 

 crystalloids, and the myelocyte is transformed into a pol}' nuclear leuco- 

 cyte. There is only one series in Sauropsida, and it is impossible to 

 uphold the idea of there being several distinct kinds of acidophilous 

 leucocytes. The idea of the specificity of leucocytes nmst })e given up. 



Muscle-fibres and Muscle-cells of the Heart of White Mouse.* 

 W. M. Baldwin finds that the conception of the cardiac muscle-fibre as 

 a cell containing fibrillae and sarcoplasm is erroneous so far as concerns 

 the adult white mouse. The terms muscle-fibre and muscle-cell are not 

 synonymous. The cuticular sarcolemma invests both the highly 

 specialized muscle-fibrillae and the sarcoplasm, and, in addition, muscle- 

 cells. These muscle-cells show a nucleus, a cell-wall, and cytoplasm 

 consisting of a spongioplasmatic network with interstices of hyaloplasm. 

 By means of the cell-wall the muscle-cells are delimited from the sarco- 

 plasm and the muscle-fibrillae. 



Branched Muscle-fibres, f — Geza Gliicksthal has studied the 

 branched muscle-fibres in the thin mucus membrane portion of the 

 boundary of the basihyoid sinus below the frog's tongue. They are 

 branches from the hypoglossus, and are readily studied in their natural 

 position. He describes their anastomoses, the literal reticulum which 

 is sometimes seen, and the brush-like shredding up at the end of a fibre. 



Degeneration of Poisoned Muscle. J — Ivar Thulin gives a detailed 

 account of the degenerative processes observed in the wing-muscles of 

 a dragon-fly {Libellula), after it had been stung by a Laphria, whose 

 poison produces paralysis. The transverse disks and granules were pale, 

 fatty degeneration had set in, the cross striping disappeared, the fibres 

 became masses of debris. 



Skin of Geckos.§— W. J. Schmidt has made an elaborate study of 

 the minute structure of the integument in Phehuma and Tarentohi. 

 He deals first with the surface and the coloration. In the latter there 

 are melanophores, porphyrophores, and guanophores to be considered. 

 He then describes the epidermis and the integumentary sense-organs. 

 The connective-tissue portion of the skin is analysed, and an account is 

 given of the layers of the corium, of the sub-cutis, of the inclusions, of 

 the blood-vessels and nerves, of the preformed breaking-zones in the 

 skin of the tail, of the cloacal sacs, and the bone in the penis-canal. 



Ependym-cells of Fish Brain.||— V. Franz has found a new kind 

 of cell in the -ependym of the fish brain. Hitherto the cells of the 

 epithelium hning the ventricle have been described as of one kind- 

 supporting cells whose peripheral processes penetrate the mass of the 



* Anat. Anzeig., xlii. (1912) pp. 177-81 (2 figs.), 

 t Arch. Mikr. Anat., Ixxxi. (1912) Heft 1, Abt. l,pp. 53-9 (1 pi.), 

 t Arch. Mikr. Anat., Ixxix. (1912) Heft 1, Abt. 1, pp. 206-22 (1 pi.). 

 § Zeitschr. wiss. Zool., c. (1912) pp. 139-258 (5 pis. and 15 figs.). 

 II Biol. Centralbl, xxxii. (1912) pp. 375-83 (8 figs.). 



