Alphitobius. | HETEROMERA. 19 
much broader than any of the species belonging to the following genera ; 
the antennz are thickened towards apex; the scutellum is triangular ; 
the legs are moderately robust, and the anterior tibie are dilated towards 
apex ; the last joint of the tarsi is strongly elongate ; the genus contains 
about twenty species, of which six are found in Europe, and the re- 
mainder are widely distributed, representatives occurring in Japan, 
India, Ceylon, the Gaboon district, South America, the Sandwich 
Islands, &c. 
The larva of Alphitobius diaperinus is described and figured by Schiddte (l.c. p. 565, 
pl. xi. fig. 1) ; in form it very closely resembles that of 7’. molitor, but has the sides 
of the segments furnished with sete; the colour is pale ferruginous beneath and fer- 
ruginous above, with the central part of each segment darker, except in middle; the 
larva of A. piceus has the upper surface entirely pale ferruginous; the insects in all 
their stages live in meal, flour, and bran. 
I. Thorax broadest at about base. . . . . . . . . A. DIAPERINUS, Panz. 
II. Thorax broadest at or near middle . . . . . . . A. PrcEus, Ol. 
A. diaperinus, Panz. (mauritanicus, Steph,, Curt., nec F.). Ovate, 
convex, pitchy black above, reddish beneath; head narrower than 
thorax, distinctly punctured, antennz short, thickened towards apex, 
pitchy, with the apex lighter ; thorax transverse, broadest at base, with 
the sides slightly rounded and gradually narrowed in front, distinctly 
and not very closely punctured ; scutellum triangular, closely punctured ; 
elytra with distinct punctured strie, interstices diffusely and rather 
strongly punctured ; legs ferruginous. LL. 5-54 mm. 
In flour; &c.; probably an introduced species; not common; London; Queen- 
borough, Kent ; Scarborough ; Northumberland and Durham district ; Scotland, in 
bakehouses, Solway and Clyde districts. Mr. Bold says that it appears to find a 
congenial climate in some of the deep hot coal mines of the Northumberland district, 
where it abounds in the stables, having probably been introduced in some of the 
horses’ food. 
A. piceus, Ol. (mauritanicus, F., nee Steph.; fagi, Panz.; Uloma 
fagt, Curt.). More oblong than the preceding, and, on the average, 
smaller, and easily distinguished by the shape of the thorax, which is 
more transverse with the sides rather strongly rounded and broadest in 
the middle ; it is also more thickly and strongly punctured ; the elytra 
are depressed on disc, with the striz less evident than in the pre- 
ceding species, and the interstices more closely punctured ; legs red. 
L. 43-5 mm. 
In old flour ; probably an introduced species; rather common ; London district ; 
Dover; Birmingham district; Rhyl; Scarborough; Manchester ; Scotland, Solway 
district ; it probably occurs in granaries in many otaer localities. 
GNATHOCERUS, Thunberg. 
The members of this genus are easily distinguished from the allied 
genera by having each of the mandibles of the male produced into a 
strong horn, which is curved inwards at apex ; the last joint of the 
o 2 
