August 8, 1913] 



SCIENCE 



199 



Tmucli to enliven and augment them will be 

 found in a book which modestly attempts to 

 lay the foundations of a phylogeny of physio- 

 logical processes. In the concluding chapter 

 occur, among others, generalized summaries 

 -of the three principal methods of food intake; 

 an interesting section on salivation with its 

 numerous differentiations; and a phylogeny 

 of the ferments in which trypsin or trypsin- 

 like substances are held to be the oldest. 

 Other matters considered in the final chapter 

 are genetic comparisons of the histological 

 processes involved in secretion and absorption, 

 the fate of absorpta, and finally a discussion 

 of " the liver question," especially interesting 

 "to those who question the validity of christen- 

 ing invertebrate organs according as their 

 <!olor, form or location happens to resemble 

 something or other in a vertebrate. This sec- 

 tion is summed up in the following paragraph : 



" The specialization of a stomach with the 

 secretion of free acid and the necessary pep- 

 sin, the formation of special glands, segre- 

 gated from the digestive epithelium, though 

 pouring their juices into the alimentary tract, 

 .the occurrence of a liver correlated with di- 

 .gestion, and finally complicated regulations in 

 the functions of these organs; all this distin- 

 guishes the digestive processes of vertebrates 

 from those of invertebrates." 



Otto Glaser 



Zoological Department, 

 Univebsity op Michigan, 

 May 13, 1913 



Die sanitarisch-patJiologische Bedeutung der 

 Insekten und verwandten Oliedertiere, 

 namentlieh ah Krankheits-Erreger und 

 KrankheUs-Vbertrager. By Emil A. Gold:. 

 Berlin, E. Friedliinder & Sohn. 1913. Pp. 

 155, Figs. 171. 



The present small volume which contains a 

 .general account of the habits of insects in 

 their relation to diseases is based on material 

 presented by Professor Goldi in a course of 

 lectures which he has been giving for a num- 

 ber of years in the University of Bern. 



In spite of its limited size it gives a very 



good presentation of such facts as can be sat- 

 isfactorily included in a university course on 

 insects and diseases, and is much better suited 

 for the general student than those portions of 

 the text-books on tropical medicine that are 

 devoted to insects. Its value lies mainly in 

 the fact that the subject is considered pri- 

 marily from the biological rather than the 

 medical standpoint, and consequently in a 

 more connected and intelligible way for this 

 class of students. 



The subject matter is perhaps somewhat dif- 

 ferent than would be indicated by the title, as 

 much emphasis is laid upon insects which live 

 partly or entirely as parasites of man and do- 

 mestic animals, to which is added a supple- 

 mentary discussion of their relation to the 

 transmission of disease. The material is di- 

 vided into three chapters : first, stinging, biting 

 and caustic insects ; second, insects and related 

 Arthropods of parasitic habits; and third, in- 

 sects and other Arthropods as carriers of dis- 

 ease. The first section is quite fully treated, 

 but the bulk of the text is devoted to the sec- 

 ond section, and the third receives rather brief 

 consideration. One might wish that the por- 

 tion relating to insects as carriers of various 

 infections had been presented in more com- 

 plete form, but this omission is more appar- 

 ent than real, for the second chapter contains 

 much material (e. g., the development of 

 trypanosomes) which one might expect to find 

 in the third. 



Goldi describes the morphology and physi- 

 ology of the poison apparatus in the Hymenop- 

 tera, scorpions, centipedes and Hemiptera and 

 points out the probable functions of the poison 

 glands in different groups. Thus in the 

 Hemiptera, spiders and centipedes, the so- 

 called poison has apparently been developed as 

 a digestive fluid. He is inclined to believe also 

 that the venom of the scorpion has a digestive 

 function in addition to its poisonous proper- 

 ties. Following this is a discussion of insects, 

 mainly caterpillars of various kinds, that are 

 provided with poisonous bristles or spines 

 which cause irritation to the skin. Numerous 

 species are figured, including a considerable 

 number from equatorial America. 



