No. 388.] REVIEWS OF RECENT LITERATURE. — 341 
contains also noteworthy contributions from the work of the author. 
The reader is struck at the outset by the breezy character of the 
author’s style, especially noticeable in the first part of the paper on 
the methods of manipulation, which contains an energetic appeal to 
study of the group by a wider circle and full directions for carrying 
on the work. In the second part the anatomy and physiology of these 
worms are discussed topically under the various systems. Among 
the more important points which are new may be mentioned a tabu- 
lation of the various forms assumed by the pharynx and cesophagus, 
together with a terminology for the same. Microchemical demonstra- 
tion of different uric compounds in preparations of the lateral fields 
strengthens the belief that the ducts in them are associated with the 
excretory function.1 The author argues for a respiratory function of 
the problematical “lateral organs ” present in varying form and devel- 
opment in all (?) the free-living forms, but wanting in the parasitic 
species, ‘and gives some personal observations on the structure of 
these little known organs in new members of the group. Various 
hints make it evident that the author has some radical improvements 
to suggest on the classification of the nematodes. It is to be hoped 
that they may be published soon, as the present confusion in the 
group is exceedingly unfortunate for all students. 
The article is illustrated by numerous exceedingly well made wood- 
cuts which represent in many cases new species unaccompanied by 
any further description than the formula after the fashion set by the 
author for nematodes, yet the advantage of accurate figures is at once 
evident. Though the cuts are small and somewhat difficult to deci- 
pher, they are very exact, and it is agreeable to see illustrations which 
are new and which represent the real conditions rather than the 
author’s diagrammatic conception of structure; were these figures 
only a little larger and more distinct they would be ideal. 
H. B. wW.. 
Origin and Development of Sense Organs. — Three popular scien- 
tific lectures on the origin and development of sense organs and sensory 
activities in the animal kingdom have been given by Dr. P. Steffan 
before the Senckenbergian Natural History Society.” In his intro- 
1 The recent researches of Nassonow, ef alii, have appeared since the publica- 
tion of the arti 
2 Steffan, e P und Entwickelung der Sinnesorgane und Sinnesthä- 
tigkeiten im Tierreiche, Ber. Senckenb. Naturf. Gesell, Frankfort a/M. (1898), 
pp. 29-69. 
