OF WASHINGTON, VOLUME XIX, 1917 129 



On July 20 last I found a female of this species attacking a 

 pupa of Melanoma i.utcrriiptnin Hald. on alder at North East, Pa. 

 These pupae were very abundant, attached by the caudal end 

 to the upper surface of the leaves. I captured the parasite and 

 placed it with pupae of the beetle in a vial. It very shortly showed 

 interest in the pupae and began its attack upon them. In ovi- 

 positing it inserted the tip of the abdomen between the pupal 

 legs and wings. The exposed pupa^ were not again examine* 1 

 until five days later when all nine were found to be parasitized. 

 Some of the parasites were in the larval and some in the pupal 

 stage, some of the latter being already black. It is evident 

 that some at least, and probably all, of the host pupae had al- 

 ready been parasitized when placed in the vial. But two, one 

 bearing larvae and one pupae, had been parasitized for the second 

 time and the minute larvae were feeding on the older parasites. 

 These younger larvae were probably the offspring of the adult- 

 captured. Both larvae and pupae of the parasites were on the 

 venter of the host and protected by the wing pads and legs. There 

 were from 3 to 7 parasites per host. Usually one larva was at- 

 tached to each of the wing pads and the rest to the venter of the 

 host. (See Plate XIV.) When the larvae had finished feeding, 

 the host pupa was sucked dry, but retained nearly its natural 

 form. The pupae of the parasite 1 were attached by their caudal 

 end to the under side of the host remains. 



At attempt was made to get the female parasite originally cap- 

 tured to attack pupae of Melasoma tremulae, but she paid no 

 attention whatever to them. There seems to be no reason why 

 the species should not attack tremulae since according to Ratze- 

 liurg, mentioned above, it was first reared from the closely allied 

 M. /><>/>iili. Its failure in this case to attack tremulae may have 

 heen due to age as the parasite died two days after the intro- 

 duction of the tri'it/iila;' pupae. 



On the 30th day of July the parasitism was so great that among 

 fifty or more pupae of the host species examined, I found only 

 three unparasit ized. 



EXPLANATION" OF PLATE XIV. 



Schizonotus xithnlili Katz. Larvae and pupae in situ beneath pupae of 



the liosl, MrltiKon/ii inlirru/t/ini/ Hald. 



TWO NEW HYDROPHILID BEETLES. 



BY K. A. SmuAK/ AND H. S. BARBER. 



A species of the Hydrophilid genus K]>/,n/</<//>Hx Lac. 1854 

 (Cerutodcrii* Muls. IS'/l non Westw. 1841; Scfi/'diiln't/ I.ec. 1874) 

 found in Arizona has been mentioned by the senior writer in his 



