250 Forty-fourth Beport o.v the State Museum 



each side of the middle with two transverse, slightly impressed areas 

 surrounded by sharply defined shining ridges. The posterior margin 



of the sixth joint is 

 slightly lobed at 

 middle, but without 

 transverse impres- 

 sions; anterior mar- 

 gin of seventh joint 

 in the middle with 

 two small stigma- 

 like impressions, and 

 on each side with 

 two large, trans- 

 verse, and shining 

 areas. The cerci 

 when viewed from 

 below, represent two 

 large irregularly- 

 oval lobes which are 

 contiguous at tip 

 and thence diverg- 

 ing. Pleurae very 

 indistinctly limited 

 by a shallow furrow 

 above and beneath. 

 The four anterior 

 Fig 11.— Pupa of the Rhinoceros beetle, Dynastes TiTYUs:pairs of abdominal 

 a, side view ; h, dorsal view. lu natural size. gpiracles are strictly 



dorsal, very large, oblong and transversely placed; the posterior pairs 

 of spiracles can not be seen in the specimens before me: they are 

 probably smaller than the anterior ones. 



Described from two specimens, both dried up and injured. 



The peculiarities of the genus in the adolescent states, as for 

 instance, the rotten-wood feeding habit of the larva, the strong, 

 peculiar odor of the larva and pupa lasting even after death, and the 

 stridulation o'f the imago, [*J are all recorded by authors. 



A Mexican Species of Dynastes. 

 In the above. Dr. Riley has referred to the description of the 

 Mexican Dynastei^ Hxjllus Chevr., by Dr. Eugene Duges, of Guanajuato, 

 Mexico. For comparison with the early stages of D. Tityus, Dr. Duges' 

 figures of D. Eyllus are herewith given, copied from his notice of the 

 species in the place above cited. 



* There is no record of the stridulation of the larva having been heard. Dr. Hamilton 

 (loc. cit.) has remarked of the imago: "While no stridulating organs are present, they 

 have the power to produce a sound that may answer the same purpose, somewhat 

 resembling that of an angry goose. The pygidium and part of the last ventral surface 

 are very hairy, and by withdrawing the abdomen from the elytra so as to admit air 

 and then suddenly forcing it out through the hair by a sudden extension, a noise is 

 produced that is rather alarming to one unacauainted with their harmlessness." 



