Verrill — Hercules Beetles from Dominica Island. 305 



Art. XXX. — Description of a New Species or Sub-species of 

 Hercules Beetles from Dominica Island, B. W. I, with 

 notes on the habits and larvce of the common species and other 

 beetles. Brief Contributions to Zoology from the Museum 

 of Yale University, JVo. IXVII ; by A. Hyatt Yerrill. 



"While collecting a very large series of Dynastes Hercules, 

 consisting of several hundred specimens, during the past two 

 years in Dominica, my attention has been frequently attracted 

 by the wide variation in coloration and markings exhibited by 

 this species. As a general rule, however, the shade of ground- 

 color, as well as the extent, shape and number of markings, 

 vary so interminably and so grade into one another that it is 

 impossible to separate any distinct color varieties which are 

 constant. Moreover, the ground-color of the elytra is almost 

 always of the same general color — a sort of straw or yellowish 

 olive — only variable in depth of color, or at the most, varying 

 from olive-ochre to greenish olive. 



A few specimens have been obtained, however, which are 

 so very distinct from all others and so remarkable in their 

 variation from the normal color of Hercules that I have 

 deemed it advisable to describe them as a new and distinct 

 species or subspecies. In fact, if coloration alone constitutes 

 a specific character among the coleoptera, then this Dynastes 

 should be considered as a new species peculiar to Dominica. 



Dynastes argentata, nov. Silvery Hercules Beetle. Male. 

 Size, general shape, processes of thorax and head, etc., indis- 

 tinguishable from Dynastes hercules. Head, thorax, lower 

 parts, legs, etc., deep jet-black, instead of dark brown or 

 purplish as in Herades. Elytra pale plumbous, silver gray 

 or grayish white, with a silvery metallic sheen. Edges of 

 elytra all around, as well as a few large, circular scattered 

 spots, intense jet-black. Hair on the posterior extremity of 

 the abdomen, tibiae, along edges of ventral segments and dorsal 

 segments of thorax, pale silvery gray or whitish. Velvet hairs 

 on lower surface of thoracic process deep orange brown or 

 ferruginous when viewed from below, but silvery white or 

 pale creamy white when seen from above or viewed in profile. 

 Hair on ventral surface of head and thorax deep ferruginous 

 or vandyke brown. 



Length (type), including thoracic process, 6 inches. Length 

 of thoracic process, 3 inches. 



Habitat, interior mountain ranges of Dominica Island, 

 Antilles. 



