1896.] Entomology. 591 
returning to issue near the mouth. Ferrill regards it as the most 
primitive form of the Cephalopoda. 
A new genus of Cottoid fishes from Puget Sound is described by Mr. 
E. C. Starks. The type species, Jordania zonope is in the Museum of 
the Leland Stanford, Jr., University. (Proceeds. Phila. Acad. Nat. 
Sci. [1895] 1896). 
Mr. J. A. Allen emphasizes the fact that the change of color in the 
plumage of birds without moulting is due to the gradual wearing off of 
the light colored edges of the feathers, combined with the more or less 
blanching of the color of certain parts. Exposure to the elements and 
friction also produce more or less marked changein color. The author 
prefaces his remarks with a brief history of origin and persistence of 
the theory unwarranted by the facts that the feathers of birds change 
color with the season independent of the process of moulting. (Bull. 
Amer. Mus. Nat. Hist., Vol. VIII, 1896.) 
ENTOMOLOGY: 
The Asymmetry of the Mouth-parts of Thysanoptera.—In 
the Bulletin of the Essex Institute, for 1890, Vol. X XII. the writer 
published a brief account of some peculiarities he had observed in the 
mouth-parts of members of this order of insects, and ventured in ex- 
planation, the hypothesis that, in these insects the mandible of the 
right side of the head is wanting, and that the parts commonly re- 
garded as mandibles are lobes of the maxillæ. Subsequently the 
writer called this anomalous condition of the mouth-parts to the atten- 
tion of members of the Entomological Club of the American Associa- 
tion for the Advancement of Science (Indianapolis meeting, August, 
1890) and presented slides showing the peculiarities described. (See — 
Canadian Entomologist, 1890, Vol. XXII, p. 215.) 
Nothing, so far as I know, has appeared in American literature 
since that time with reference to the matter, and the old view concern- 
ing the structure of the mouth seems to be still current. In Prof. 
J. H. Comstock’s excellent manual, recently issued (1895) the labrum 
is represented as perfectly symmetrical, the parts considered by him to 
be mandibles are incompletely represented, and no mention is made of 
1 Edited by Clarence M. Weed, New Hampshire College, Durham, N. H. 
