POLYDROSUS. 209 
and P. ochreus, Fall); two species, however, are known from I.ower California. The 
eleven forms now added from within our limits are closely related to some of those 
inhabiting the Palearctic region, P. longicornis, indeed, being a near ally of P. pterygo- 
malis, Boh. ‘The basally connate claws is perhaps the best character by which to 
distinguish Polydrosus from most of the allied genera, and the sharply defined, narrow 
scrobes separate it from Phyllobius. ‘The antenne are extremely slender in most of 
the forms here described; the femora are unarmed; and the scrobes vary in length 
according to the species, sometimes extending to the lower surface of the rostrum. 
These insects attack Quercus, Salix, Alnus, Corylus, &c., and many more species will 
doubtless be found to occur in the New World *. The Central-American forms may 
be tabulated thus :— 
a. Antenne long, the outer joints of the funiculus oblong or obconic, the scape 
nearly or quite reaching the front of the prothorax. 
a’, Scrobes shorter ; antennz slender; prothorax cylindrical or subcylindrical. 
a’, Klytra with moderately prominent humeri; head shorter. 
a. wee surface without green scales. 
. Elytra sharply fusco-fasciate. . 2. 2 1. 2 ew ew ee ee fuscofasciatis. 
oe Elytra faintly flavo-maculate. . . . 1. . . re flavonotatus. 
*, Upper surface with green or pale cupreous scales, the elytra at least 
maculate ; under surface with fine hairs only down the middle. 
c‘, Scales shining golden-green; elytra with small dark patches; eyes 
moderately large 2. 2... . ee ee eee ee eee longicornis. 
d‘. Scales green or pale cupreous ; prothorax vittate and elytra maculate ; 
eyes larger. 6 6 ee ee ee ee ee ee we mutabilisy. 
c’. Upper surface with green and brown scales ; elytra obliquely fasciate . partitus. 
d*. Upper surface uniformly clothed with green scales . . . . . ~~ tmmaculatus. 
b>. Elytra with more prominent humeri ; head longer; upper surface with 
green or greyish scales. 2 0. 1 1 ee eee ee ee macrocephalus. 
b'. Serobes longer, descending to lower surface of rostrum; antenne stouter ; 
elytra longer. 
©. Prothorax subconical; upper and under surfaces uniformly clothed with 
green scales 2. 1 1 ee ee ee ee ee ainplipennis. 
d®, Prothorax cylindrical; upper surface with coppery-brown and under 
surface with green scales . . . Coe ee ee ee ew ee) Chlorogaster. 
6. Antenne shorter, the outer joints of the faniculus moniliform, joint 2 small; 
scrobes descending; prothorax short; elytra somewhat acuminate; upper 
surface uniformly clothed with green or metallic scales. 
ce’. Prothorax obliquely narrowed anteriorly ; elytra with very fine short hairs. acuminatus. 
d', Prothorax strongly transverse, slightly narrowed anteriorly ; elytra strongly 
setose 2. ee ee ee ee ee ee ee ee pallidisetis. 
* Two or three others are represented in our collection by worn examples only. 
BIOL, CENTR.-AMER., Coleopt., Vol. IV. Pt. 3, May 1911. 9 BE 
