34 BULLETIN 66, UNITED STATES NATIONAL MUSEUM. 



b. In stylopized male bees the copulatory apparatus becomes 

 diminished in length, width, and curvature. 



c. Stylopized leafhoppers can hardly be determined on account of 

 alterations of the genitalia according to Prof. E. D. Ball. 



That parasitism does not entirely prohibit copulation is evidenced 

 by several records. Mr. Dury took a female Leionotus foraminatus 

 Saussure, containing a female parasite in the third segment, while in 

 copulation on August 10, 1901, at Cincinnati, Ohio. 



Perkins (1891) showed that males containing female stylops were 

 "apparently capable of reproduction." He also cites (1905) Piffard 

 as collecting a stylopized male bee copulating, but probably the 

 most conclusive record of all is that of a male Tetigonia, "bearing 

 two great male puparia and two mature female parasites, which was 

 in copula with a female carrying three or four parasites." 



On April 27, 1900, Mr. Crawford took a male and female Andrena 

 craurfordi in copula, each of which bore an empty male puparium. On 

 April 28 he took a pair in which the male was unparasitized and the 

 female bore two female parasites. On April 30 the author took a pair 

 in which the male bore a female parasite and the female was 

 unparasitized. 



Owing to Mr. Crawford's knowledge of the available characters in 

 Apoidea, the writer has submitted all of his parasitized material to 

 him for examination. The results of Mr. Crawford's observations 

 upon Andrena crawfordi are given below, and the writer feels it incum- 

 bent upon him to acknowledge the services of Mr. Crawford in this 

 respect and upon tins point. 



1. Puncturation of abdomen less strong, punctures finer and 

 sparser; especially noted on second segment. 



2. In females with male parasites the basal joint of the hind tarsi 

 is narrower, approaching the shape of the corresponding joint of the 

 male tarsi ; this joint not noticeably narrowed in female with female 

 parasites. 



3. Scopa of parasitized female thinner, plumosity shorter, not so 

 silky. 



4. Out of 6 males with male parasites 2 show the second transverse 

 cubital gone in both wings; 1 has stubs at each end, however, in 

 right wing; 1 has the first transverse cubital slightly interrupted in 

 both wings. Out of about 110 nonparasitized males none show any 

 variation. 



5. Out of 38 females with male parasites 1 has the left wing with 

 3 submarginals, the right wing with 2 submarginals ; 1 has 2 sub- 

 marginals in both wings but right wing with a stub of the nervure; 

 1 has first transverse cubital of the left wing one-half gone; 45 non- 

 parasitized females show no variation. 



