OF WASHINGTON, VOLUME XIII, I'.lll. 21 



FACTS IN THE LIFE HISTORY OF GONIOPS CHRYSOCOMA. 



[Diptera; Tabanidse.] 

 BY W. L. McATEE. 



Interesting features of the behavior of the tabauid (ion/ops 

 chrysocoma (Osteu-Sacken) were observed on Plummer's 

 Island, Maryland, during the season of 1910. While assem- 

 bling this and other data for an article embodying all avail- 

 able information on this fly in the District of Columbia faunal 

 region, it was found that Mr. Theodore Pergande had col- 

 lected, years ago, two full-grown larvae, which stage of 

 Goniops, as well as the pupa, remain undescribed. One of 

 these larvae was preserved, the other allowed to pupate. The 

 pupa was bred and preserved with the female imago which 

 emerged. The instance adds but another to the long list of 

 contributions to life histories made during a lifetime of en- 

 thusiastic collecting and careful breeding of insects by Mr. 

 Pergande. Great credit is due him for valuable work in this 

 much-neglected field. 



Through the courtesy of Dr. L. O. Howard, Chief of the 

 Bureau of Entomology, U. S. Department of Agriculture, I 

 am enabled to describe and figure this larva and pupa. 



The eggs and first-stage larvae of Goniops were described 

 and figured by W. R. Walton in the Entomological News for 

 December, 1908 (vol. xix, No. 10, pp. 464-465; pi. xxn), 

 He concludes that the incubation period is from seven to ten 

 days, although according to the dates g-iven (July a mis- 

 print?) it would be much longer. The eggs of Gon/ops have 

 been seen during each of the last three years on Plummer's 

 Island, Maryland. On June 26, 1908, H. S. Barber collected 

 a female and a large, greenish-white egg-mass which was laid 

 on the underside of an oak leaf about 8 feet above the 

 ground (See PI. I, figs. 3, 4, 5). The larvae hatched June 28. 



In 1910 the writer found four egg-masses on July 3 and two 

 on July 10. One of the first four egg-masses was collected. 

 The larvae hatched July 7. Another had been deserted by 

 the female by July 10. The outer layers of eggs were black, 

 and from them issued, on July 11, numerous proctrotrypids, 

 which J. C. Crawford says are Telenomus, probably an unde- 

 scribed species. The two remaining egg-masses of the lot 

 found July 3 were covered by the females until July 10, a 

 period of a week, during which time manv eggs were added. 

 These eggs, and the two masses discovered July 10 as well, were 

 hatched by July 17. They were deposited on the undersides 



