OF WASHINGTON. 11 



of the stigmal plates had been used for many years by various 

 authors — Berlese, Canestrini, Stoll, etc. — and that Neumann, 

 in his Revision of the Ixodidse, had used the sculpture of 

 these plates, as, for example, in Dcrmacentor variegatus. Mr. 

 Banks also stated that the sculpture of the stigmal plates can 

 usually be made out by the aid of a |-inch lens. He thought 

 that other characters are of equal value and especially men- 

 tioned the porose areas. These, also, have been used by 

 Neumann. 



— Mr. Barber exhibited a microscopic mount of a species of 

 the genus Polyctenes, collected at Sapucay, Paraguay, by Mr. 

 W. T. Foster. These insects are parasitic on bats of the 

 genus Molossus, and were taken by Mr. Foster on M. rufus 

 and M. cerastes. The genus was proposed by Westwood,* 

 who figured and described a species from Jamaica, P. fum- 

 ariiis, and another from China, placing it in the Family 

 Polyctenidae, of the order Anoplura. Waterhouse'' consid- 

 ered the genus to be dipterous, and described two new species 

 from Java and Madras, and a new genus, Euctenodes, which 

 he placed in this family, but which is allied to the dipterous 

 genus Strebla. A year later he described another species,*^ 

 P. longiceps, from Guatemala, on Molossus abrasus, and at the 

 same time recognized its affinity to the Hemiptera and the 

 impossibility of placing it amongst the Diptera. 



In spite of the remarkable superficial resemblance of these 

 insects to certain of the pupiparous Diptera, there is no doubt 

 as to their being true Hemiptera. The mouth parts, the an- 

 tennae, and legs all bear out this relationship, and the char- 

 acters which they have in common with the pupipara are 

 distinctly secondary in their nature, and are such as would 

 naturally be developed through the peculiar habits of the in- 

 sects. Such secondary characters are the combs on the head 

 and thorax, the unusually formed tarsal claws, etc., which are 

 very much the same in the fleas, the pupipara, and in this 

 genus, and which are unquestionably of assistance in clinging 



' Thesaurus Entomologicus Oxoniensis, 1874, P- 198, pis. 38, 39, 40. 

 " Trans. Ent. Soc. Lond., 1879, p. 309, pis. 9 and 10. 

 " Ibid., 1880, p. 319, pi. 10. 



