164 PROCEEDINGS OF THE NATIONAL MUSEUM VOL, 92 
ANOXIA PILOSA Fabricius 
The males of the three European species before me, pé/osa Fabricius, 
villosa Fabricius, and orientalis Krynicky, differ from the male of the 
American Polyphylla gracilis Horn as follows: The terminal seg- 
ment of the maxillary palpus is broader and strongly impressed 
dorsally; the tarsi are subequal to or shorter than their respective 
tibiae; the antenna is 10-segmented with 5-segmented club; and the 
tarsal tooth is much more strongly inclined to one side. 
In the female, A. pilosa has a 4-segmented and P. gracilis a 5-seg- 
mented antennal club, while both have the front tibiae bidentate. The 
males of all the United States and the Neotropical species of Poly- 
phylla differ from the males of the examined Anowia in having biden- 
tate front tibiae, whereas the Anowia males have no external teeth 
on the front tibiae other than the blunt outer apical angle. 
The North American Thyce fieldi Fall is the only species of that 
related genus having unidentate front tibia in the male, and it is 
doubtful whether the number of teeth on the front tibia offers a 
character of more than subgeneric value. 
RHIZOTROGUS (AMPHIMALLON) SOLSTITIALIS (Linnaeus) 
The adult of this European species, although close to the American 
species of Phyllophaga, belongs to a distinct genus. The male 
solstitialis differs from the male of our Phyllophaga as follows: The 
tarsal segments are thicker; the front tibiae are unidentate or second 
tooth is hardly obvious; the middle tibiae have a very incomplete 
or no carina; the claws are a little thicker; the sixth abdominal seg- 
ment is plane and without sexual differentiation; and the genitalia 
are quite tubular and symmetrical but still approach somewhat 
closely in form the genitalia of certain neotropical species. The 
major distinction between Rhizotrogus solstitialis and our continental 
Phyllophaga is the lack of distinct sexual differences on the abdomen. 
Genus ANCYLONYCHA Dejean 
Ancylonycha DEJEAN, Catalogue des coléoptéres de la collection de M. le Comte 
Dejean, ed. 2, p. 160, 1833. (Type: Melolontha serrata Fabricius, the third 
included species; designated by Duponchel, Dict. Univ. Hist. Nat., vol. 1, 
p. 526, 1849.) 
Holotrichia Horr, The coleopterist’s manual, vol. 1, p. 99, 1837. (Type: Melo- 
lontha serrata Fabricius, by original designation. ) 
Duponchel designated M. serrata Fabricius as genotype of Ancyl- 
onycha, and since this species is included in the original Dejean set-up, 
the type designation is valid, and the inclusion of a described species 
in the genus validates the name Ancylonycha Dejean of 1833. 
