1898.] ENTOMOLOGICAL NEWS. 73 



hesitation in stating that exstriata Calvert is specifically identical with 

 denticolle Burm., but it is evident that this discovery breaks down the 

 only general distinction separating the two groups of genera represented 

 by Ischnura and Nehalennia respectively. I find, moreover, that in /. 

 verticalis Say, I. perparva Selys and I. cervula Selys female individuals 

 of one and the same species exist which have this spine absent, extremely 

 small or quite distinct. — Philip P. Calvert. 



Odonata. The first filling of the trachea with air. — Within 

 half an hour after hatching from the egg, the young larva of Sympetrum 

 {Diplax) vicinutn Hagen — and the same is true for Libellula quadrimacu- 

 lata L. and Orthetrum cancellatum L., as I observed at Jena, in June, 

 1896, — makes its first moult. Previously its tracheae, though visible, con- 

 tain no air. In watching some larvae of vicinutn execute this first moult 

 recently (January, 1898), I observed that air first appears in the tracheal 

 system, in the thoracic portion of the right, main, dorsal trachea and 

 flows thence both forwards into the cephalic, and backwards into the ab- 

 dominal tracheae, consequently filling the tracheoles of the rectal tracheal 

 gills at a measurably later period. I believe that this observation is new, 

 at least for the Odonata. 1 regret that I could not determine precisely 

 where the air enters, nor how, nor whether the air which early appears 

 in the left, main, dorsal trachea enters independently, or from branches 

 connecting it with the right dorsal trunk. 1 hope that detailed statements 

 may appear later. — Philip P. Calvert. 



News of the Department of Insects, U. S. National Museum. — 

 The collection of insects of the U. S. National Museum is rapidly increas- 

 ing. A great donation, the details of which have just been completed, is 

 the large Hubbard and Schwarz collection of Coleoptera. This is one 

 of the first collections of Coleoptera in the United States. It comprises 

 from 10,000 to 12,000 species brought together by Messrs. Hubbard and 

 Schwarz during the last twenty-five years. It has especial value from its 

 fine condition and accurate labelling, affording possibly the best source 

 of information regarding geographical distribution. This collection adds 

 about 3000 species to the collection of Coleoptera of the Museum. It 

 contains a moderate number of types, but a large number of co-types of 

 the species described by LeConte and Horn. It also contains some ex- 

 otics, notably a good collection of West Indian micro-Coleoptera, and is 

 practically unique in its large series of coleopterous larvae and pupae in 

 alcohol. 



The death of Mr. M. L. Linell, in the spring of 1897, was a severe blow 

 to the Department, but a re-arrangement has been effected by which an 

 excellent working force has been secuied. The Department has been 

 extremely fortunate in attaching to it Dr. Harrison G. Dyar. Since the 

 departure of Dr. John B. Smith there has practically been no lepidopterist 

 in Washington, and Dr. Dyar's advent is especially welcome. He has 

 entirely re-arranged the collection of Lepidoptera and has deposited in 



