Zoology 145 



surface by absorbing water against the osmotic pressure of the salts of sea-water. 

 On windy days they can sink by increasing their specific gravity. Anesthetics, acids, 

 alkalies, KCN, and the pure salts of sea-water do not interfere with this regulating 

 mechanism if the animal remain alive. A study is also made of the light-produc- 

 tion in Noctiluca. 



Treadwell describes 11 new species of Annelids from Florida, Porto Rico, and 

 Bermuda. 



Jordan contributes four papers; one upon the microscopic structure of striped 

 muscle of Limulus. 



In the second paper which deals with hemopoiesis in the mongoose embryo he 

 concludes that the mesenchyne is a fundamental hemogenic tissue. Both endo- 

 thelium and mesothelium may at early stages give rise to hemoblasts. The author 

 supports the monophyletic theory and maintains that the primitive leucocytes appear 

 before the erythrocytes. 



In another paper Professor Jordan studies the origin and early history of the 

 germ cells in the loggerhead turtle which are very similar to that in Chrysemys, 

 or the dog-fish. 



Jordan's fourth paper describes the cause of the temporary closure of the origi- 

 nally open esophagus of the embryo turtle and the final re-^establishment of its 

 lumen. This temporary closure of the esophagus appears to be a device to prevent 

 the entrance of yolk material into the lung during early stages of development. 



No. 252. Papers from the Department of Marine Biology of the Carnegie Institu- 

 tion of Washington. Vol. XII. Octavo, v+258 pages, 29 plates, 28 

 figs. Published 1918. Price $5.00. 

 This book contains the following papers, not sold separately: 



FOWLER, HENRY W. Some Amphibians and Reptiles from Porto Rico and the Virgin 



Islands. 15 pp., n pis., 6 figs. 

 SILVESTER, CHARLES F. Fishes New to the Fauna of Porto Rico, with Descriptions 



of Eight New Species. 8 pp., 4 pis. 

 GUDGER, E. W. Oral Gestation in the Gaff -topsail Catfish: Felichthys felis. 28 



pp., 4 pis. 

 GODGER, E. W. Sphyrana barracuda: its Morphology, Habits, and History. 56 pp., 



7 pis., 5 figs. 



BOWMAN, H. H. M. Botanical Ecology of the Dry Tortugas. 30 pp., 6 pis., 7 figs. 

 WHITE, E. GRACE. The Origin of the Electric Organs in Astroscopes guttatus. 44 



pp., 7 pis., i fig. 



MAYER, A. G. Toxic Effects due to High Temperature. 6 pp. 

 MAYER, A. G. Nerve-conduction in Diluted and in Concentrated Sea-water. 3 



pp., i fig. 

 BALL, S. C. The Migration of Insects to Rebecca Shoal Light-Station and the 



Tortugas Islands, with special reference to Mosquitoes and Flies. 30 pp. 

 CARY, LEWIS R. A Study of Respiration in Alcyonaria. 7 pp. 

 MCCLENDON, J. F. On Changes in the Sea and their Relation to Organisms. 47 



pp., 8 figs. 



Fowler describes or lists 23 species of Amphibians and reptiles from Porto Rico 

 and the Virgin Islands, 7 of which are figured. 



Silvester describes or lists 21 species of fishes from Porto Rico, 8 of which are 

 new to science, and are illustrated by colored figures. 



Gudger describes the habit of oral gestation in the Gaff-topsail catfish. The 

 male carries the eggs in his mouth until they develop into young fishes; the female 

 is cannibalistic and readily devours her own eggs or those of other females. The 

 male does not take food during the period of gestation. 



Gudger in a second paper gives an exhaustive account of the habits, morphology, 

 and literature relating to the barracuda of Florida and the West Indies, the paper 

 being illustrated by numerous figures and citations from many interesting works 

 by old authors. 



Bowman describes the ecology distributions and associations of the dry-climate 

 plants of the Tortugas Islands, and especially the changes which have occurred in 

 recent years. The paper is fully illustrated. 



E. Grace White shows that four of the eye muscles of Astroscopus guttatus give 

 rise to the electric organs of this fish. These organs begin to differentiate before 

 the embryo is 14 mm. in length. The anatomy of the organs in various stages 

 of development is fully discussed. The paper cites the important literature of the 

 subject and is fully illustrated. 



