ENEMIES AND THEIR INFLUENCE. 



397 





Fig. 333. 



Fig. 334. 



Fig. 333. Magnified cell of parasitic hynienopter, probably Aco- 

 loides saitidis. Fig. 334. Saltigrade cocoon, with parasitic 

 cells enclosed, somewhat mag-nified. The fly on the edge is 

 about natural size. 



October, 1884, Mr. F. M. Webster sent me from Oxford, Indiana, a 

 parasitized cocoon, evidently of some Saltigrade species, which appeared to 

 be that of Phidippus morsitans. The cocoon contained within the outer 

 flossy case about eighty cells or pupa cases and a num- 

 ber of mature black hymenopterous insects about one- 

 eighth inch long. (Fig. 334.) The cells were ovoid, 

 gray, blackish at the closed 

 end, probably from excre- 

 tions from the enclosed lar- 

 vae. One end was cut open, 

 showing where the insects 

 had escaped. (Fig. 333.) 

 With the exception of a few 

 hard, dry, yellowish l)rown 

 examples, all the eggs of 

 the spiders had disappeared. 

 The specimens were sent to Mr. L. O. Howard,' who thought them to be 

 Proctotrupids, belonging to the subfamily Scelionina>, and seeming to form 

 an entirely new genus. '-^ 



This gei;tleman has lately published '■^ a description of a liymeno})terous 

 parasite on spiders sent to him by Mr. L. Bruner, of Lincoln, Nebraska, 

 which was collected from the eggs of a Saltigrade, Saitis pulex. 

 The eggs of this spider are a little more than a millimetre in 

 circumference, and each egg harbors but one parasite, which 

 issues by splitting the egg case open, rather than by gnawing a 

 hole. This insect Ijelongs to the same family and subfamily and is prob- 

 ably the same species as that col- 

 lected by Mr. Webster. Mr. How- 

 ard has named it Acoloides saitidis, 

 and a copy of the drawing of the 

 insect is given at Fig. 335. In the 

 same connection Mr. Howard de- 

 scribes, under the name of Bieus 

 americanus, a new species, a mi- 

 nute wingless Scelioninse, from spec- 

 imens sent him ten j^ears ago by 



americanus. (After Howard.) Natural sizes shown Dr. MarX, wllO appears tO liaVC TC- 



^^^^^^ them from Col. Nicholas 

 Pike, of Brooklyn, New York. They are labeled : " Parasites in spider's 

 eggs in an orange cocoon." Dr. Marx, after examining the eggs, expressed 

 the opinion that the host from which these little jaarasites were established 



Salti- 

 grade 

 Guests 



Fig. 335. Fig. 336. 



Fig. 335. Acoloides saitidis. a hymenopterous parasite 

 on the Saltigrade, Saitis pule.x. Fig. 336. Bgeus 



' Bureau of Entomology, Department of Agriculture, Washington, D. C'. 

 2 Proceed. Acad. Nat. 8ci., Philadelphia, 1S84, jiaiic I'iM. 

 2 " Insect Life," Vol. II., No. H, 1890, page aiy. 



