10 CYRTIDAE OF NORTH AMERICA 



In Acrocera (Plate I, figs. 4 and 9) there is a great reduction and 

 transposing of veins. The origin of the first, fourth and fifth 

 longitudinal veins can be clearly traced, but their subsequent 

 development is confused because of the suppressions of long veins 

 and cross-veins. The praefurca arises from the first longitudinal 

 vein and the second longitudinal is present in some and lacking in 

 others. The majority of Cyrtidae have the second vein com- 

 plete, in some it is missing and in some represented by a stump, 

 either at the distal or the proximal end. Thus at times there is 

 one, and in other cases no submarginal cell. Acrocera himaculata 

 is the best example of stunting, the stump being in the wing mar- 

 gin. This proves that the total disappearance is not a conse- 

 quence of coalescence with the first vein, but of obliteration. 

 Osten Sacken thus correctly infers that the obliteration of the 

 second vein in Acrocera is not a deep-seated character at all, and 

 not an index of a corresponding change in the rest of the organism. 

 Dr. Grifiini expressed this opinion when he cast the genus Pora- 

 crocera into synonomy. Mik united the species of Acrocera which 

 lacked the second vein into a new genus which he called Para- 

 crocera. There is no discal cross- vein, the almost upright 

 vein just after the middle of the wing is a portion of the fourth 

 longitudinal vein (as in Pterodontia) . The almost upright vein 

 connecting the fourth and fifth longitudinal veins is the upper 

 branch of the fifth vein. 



A few Bombyliidae (such as the genus Glabella) have at times 

 been mistakenly placed in the Cyrtidae. There are analogous 

 insects as far as shape goes in Coleoptera, Homoptera and Orth- 

 optera, and affinities can be seen with the hump-backed Bomby- 

 liidae in some instances. Like the parasitic Oestridae and Tach- 

 inidae these flies have very large thoracal squamae. Aldrich 

 placed the Cyrtidae between the Nemestrinidae and the Bom- 

 byliidae in his "Catalogue," and I believe this is their proper posi- 

 tion in the system. 



Habits of the Cyrtidae 



The adults of Lasia and Eulonchus arc known to suck the nectar 

 of flowers, Ijut most of the genera, having undeveloped mouth- 

 parts, can take no nourishment. Philippi mentions the finding 

 of adults of Megalybus on flowers — "the larvae live, it seems, in 

 wood, at least my son Karl in Dec. 18G3 found a fly of this species 



