1048 The American Naturalist. [December,. 
trache of the Arachnids being derived from it. And with these 
facts these is left no ground for those who regard the * Tracheata’ as a. 
natural group of the animal kingdom." 
Hexapopa.—Schott has a monograph of palarctic Thysanures in 
Vol. xxv of the Handlingar of the Swedish Academy, 153 species and 
varieties are enumerated, of which 9 are new. Seven plates illustrate 
the article, which cannot be neglected by entomologists. 
A most interesting paper on the relations between attitude and color 
of European butterflies is given by Dr. Standfuss in the Zürich Society’s. 
Vierteljahrschrift for 1894. 
Hexapopa.—Scudder gives ? a synopsis of the ringless locustarians 
of the tribe Ceuthophili. Six genera and 67 species are described. 
Morrusca.—Dall has monographed " the genus Gnathodon. From 
a consideration of large suites of specimens, and of young as well as 
old, and also from a study of the soft parts, he concludes that the genus 
is distinctly Mactroid in character. Ten species and varieties are enu- 
merated. 
Dr. Stearns " catalogues, with notes, a collection of shells from "Lower 
California and adjacent waters, made b . J. Fisher in 1876, to- 
gether with those of other collectors. The paper has great value in 
matters of synonymy and geographical limits of species. 
A pellóff records * the presence of several North American species of 
Cephalopods on the Norwegian coasts, and describes an example of 
Eledone cirrhosa in which the third right arm of both sides is hecotoco- 
tylized. 
Frsues.—Gill shows” that our American pike perches must con- 
tinue to bear the generic name Stizostedion, and that the European 
Lucioperca marina has more affinities with the other European species 
than with any American forms 
The same author also pleads” for the use of Pociliidz instead of 
Cyprinodontide, and discusses the nomenclature of the Lampreys, dis- 
carding his previously advanced name of Ammocotes for the genus 
petra. He further makes a family Mordaciide for the genus 
'5 Proc, Amer. Acad. Arts and Sciences, xxx, 1894. 
1% Proc. U. S. Nat. Mus., xvii, 1894. 
MTom. Cit., 1894. 
18 Bergens Museums Aarbog for 1892, 1893. 
19 Proc. U. S. Nat. Mus., xvii, 1894. 
L. c. 
