4H THE POPULAR SCIENCE MONTHLY. 



LITERARY NOTICES. 



Jonxs IIorKiN's University Studies from 

 the Biological Laboratory. Edited 

 by Professors Newell Martin and W. 

 K. Brooks. Vol. III. Baltimore, Md. : 

 X. Murray, publisher. 



When a former volume of this publica- 

 tion was reviewed in these pages, we com- 

 mended the intelligence and liberality of 

 the trustees for recognizing the importance 

 of supporting a scientific publication of so 

 special a character as this one. It is an 

 encouraging omen for science in this coun- 

 try, that universities are recognizing the 

 importance of publishing the results of 

 their laboratory-work. Aside from the hon- 

 or which an institution derives from an is- 

 sue of this nature, there is good reason to 

 believe that such a publication is a proper 

 investment for a library fund. Every col- 

 lege library needs upon its shelves the 

 journals and transactions of home and for- 

 eign societies. Instead, then, of subscribing 

 for many of these, it were better to invest 

 the same amount in a publication which, by 

 judicious exchange, accomplishes the same 

 result, with the added satisfaction of con- 

 tributing its scientific work to the world. 

 The numbers before us maintain the high 

 standard of the previous volumes. Space 



a sexually mature condition in sexual 

 pouches. A segmentation of the embryo 

 which is exceptionally among annelids per- 

 fectly regular, and the origin of the ventral 

 nerve-cord from the ectoderm as a bilateral 

 structure." Henry Leslie Osborn gives the 

 results of his studies on the gill in some 

 forms of prosobranchiate mollusca. Pro- 

 fessor Lankester, in his valuable paper on 

 mollusca, in the last edition of the " Ency- 

 clopaedia Britannica," states his belief that 

 the primitive gill of the mollusca was a 

 ctenidium, a stalk with plates very much 

 like the gill of Chiton and Fissurella. Mr. 

 Osborn is led, however, from his embryo- 

 logical studies, to question this view, and 

 to doubt whether the ctenidium form rep- 

 resents the primitive form of molluscan gill, 

 and shows that in the ctenobranchs the gill 

 is not a ctenidium, but a very much simpler 

 organ. Its form compares closely with the 

 primitive lamellibranchiate gill. 



" Notes on the Composition of the Blood 

 and Lymph of the Slider Terrapin," and al- 

 so " On the Origin of the Fibrin formed in 

 the Coagulation of Blood," by W. H. How- 

 ell. Both these memoirs are too technical 

 for a short review. 



"On the Action of Acid, Atropia, and 

 Convallaria on the Heart ; with some Ob- 



will permit hardly more than a mention by i scrvations on the Influence of Oxygenated 



title. The volume commences with a mem- 

 oir entitled " Significance of the Larval Skin 

 of Decapods," by n. W. Conn. The author 

 states that Crustacea are a particularly fa- 

 vorable group for the study of phylogeny, 

 and then proceeds to show the significance of 

 the larval skin, and a very interesting discus- 

 sion is given as to the ancestral form of Crus- 

 tacea. From his study of the larval cuticle 

 in the long- and short-tailed decapods, the 

 author infers that " all decapods are to be 

 referred back to a form similar to the proto- 

 zoa (zoea), in which the segments of the 

 thorax and probably of the abdomen were 

 present, and whose antenna} were locomo- 

 tive organs." Mr. Conn has another paper 

 on the " Life History of Thalassemia," a pe- 

 culiar worm which lives within the empty 

 shell of mellita or "sand dollar." ne finds, 

 among other interesting conditions, "the 

 origin of the ova and spermatozoa as 

 modified peritoneal cells, their growth in 

 the body cavity, and their preservation in 



and Non-Oxygenated Blood, and Blood in 

 Various Degrees of Dilution," by H. G. 

 Beyer. The title sufficiently indicates the 

 scope of this paper, which will be more 

 interesting to students of therapeutics, and 

 to these and to physicians we commend it. 



" The Action of Intermittent Pressure 

 and of Defibrinated Blood upon the Blood- 

 vessels of the Frog and Terrapin," by 

 Louis T. Stevens and Frederic S. Lee. 

 This paper, like the last, is mentioned by 

 title and for the same reason. 



" Cranial Muscles of Amia calva, with 

 a Consideration of the Relations of the 

 Post-Occipital and Hypoglossal Nerves in 

 the Various Vertebrate Groups," by J. Play- 

 fair McMurrich. His investigations lead him 

 to believe that the primitive Elasmobranclis, 

 the Ganoids, and the Tclcostci, to be con- 

 nected along one line, and the Ci/chstoma, 

 Dipnoi, and Amphibia along another. 



" On the Endings of the Motor Nerves in 

 the Voluntary Muscles of the Frog," by Chr. 



