58 Bulletin of the Brooklyn Entomological Society Vol. XVI 



ILLUSTRATIONS OF THE MALE HOOKS IN NABIS 

 (NABIDJE, HEMIPTERA).! 



By Dorothy J. Hickman, Smith College, Northampton, Mass. 



In the genus Nabis the males are provided with a pair of 

 copulatory hooks (hami), which are visible without dissection and 

 are often useful in the determination of species, as their shape 

 is generally characteristic. This was recognized long ago by 

 Renter who published in 1873 ^ paper treating several American 

 species, among others, with figures of moderate accuracy.^ In 

 some recent work on the genus^ these genital characters have 

 been employed, but without figures, so that it seems appropriate 

 to offer the accompanying illustrations as a further contribution 

 to the study of this group. 



All the American species are figured, with the exception of 

 crassipes Reut., heidemanni Rent., spinicrus Rent., inscriptus 

 Kirby, and kalmii Reut., of which the last two at least are not 

 definitely understood at present. 



There is little real variability in the form of the hooks within 

 the species, even in ferus, but the structure is so irregular that the 

 aspect changes somewhat with every shift in lighting and posi- 

 tion. Thus no attempt is made to indicate the details of surface 

 sculpture, transparency, etc. In sordidus, however, we find a con- 

 siderable variation in form, of which the extremes are shown in 

 Figs. 3 and 4. 



Acknowledgment is made to Mr. H. G. Barber for the loan of 

 several valuable specimens and to Dr. H. M. Parshley for the use 

 of material and for advice during the course of the work. 



The drawings were made free-hand with the aid of a binocular 

 microscope (10 X oc, 25 mm. obj.) and the figures are magnified 

 about 50 diameters. 



1 Contributions from the Department of Zoology, Smith College, No. 8. 

 2Reuter, " Nabid^ nov«," Ofv. K. Vet.-Ak. Forh., XXIX; No. 6: 79- 

 96, pi. 8, 1872 (1873). 



3 Parshley, " Hem. Peaks Island," Can. Ent., LII : 80-87, 1920. 



