174 ENTOMOLOGICAL NEWS. [May, '04 



nomenclature in the Rhopalocera, and it was finally agreed 

 that Dr. Skinner's names as given in the new Smith's list 

 would be best to use. 



Mr. Tower thereupon proceeded with his talk on color vari- 

 ations in insects as affected by climatic changes. He gave a 

 very interesting resume of the results achieved by various 

 prominent entomologists in subjecting fresh pupae of butter- 

 flies to freezing temperature, etc., and went more into detail 

 on the experiments he is now conducting with the common 

 potato beetle as a subject. After a little informal talk the 

 meeting adjourned at 9.50 P.M. A. KWIAT, Recorder. 



A meeting of the Entomological Section of the Academy of 

 Natural Sciences of Philadelphia was held March 24th, Mr. 

 H. W. Wenzel, Vice-Director, presiding. Thirteen persons 

 were present. Dr. Calvert exhibited a collection of nymphs 

 of Odonata from New Jersey which he had identified for Prof. 

 John B. Smith. The determinations were made from Prof. 

 Needham's keys and descriptions which he had found very 

 satisfactory. Among these specimens were some which agreed 

 with the skin of the nymph from which Mr. H. L,. Viereck had 

 reared Micrathyria berenice Drury, as mentioned in the NEWS, 

 Vol. xiv, p. 276. 



The nymph of this species, hitherto undescribed may be re- 

 cognized by the following characters. Abdomen somewhat 

 similar in outline, when viewed from above, to that of Libel- 

 lula basalis ; without dorsal hooks, their place being taken by 

 a carinate tubercle on each of segments 3-9, this tubercle quite 

 hairy, especially on 6-9 ; only 8 and 9 with lateral hooks, those 

 on 8 being about one-fifth as long as the mid-dorsal length of 

 9, those on 9 subequal to the mid-dorsal length of 10, both 

 hooks incurved, those of 9 more strongly. Inferior appendages 

 subequal to the mid-dorsal length of 9, laterals half shorter, 

 superior one-fourth shorter. Eyes quite prominent, reaching 

 back to almost half the length of the head, which last is much 

 narrower behind them. Mental setae 10-11, the fourth to 

 seventh from outer side longest. Lateral labial setae 9-10, 

 movable hook almost straight, 11-12 crenulations on the oppo- 

 sing (distal) edges of the lateral labial lobes. Length of the 



