416 | THE AMERICAN NATURALIST. [VoL. XXXIII. 
not differ so much, and I am inclined to treat them only as 
tribes of one subfamily, thus: 
Tribe, Margarodini. Subterranean; anterior legs of both 
sexes (adults) adapted for digging. Tribe, Xylococcini. Arbo- 
real; anterior legs normal. 
The striking character of the adult Margarodes, especially 
(because least expected) in the 3, is that of the anterior legs. 
The ¢ of Porphyrophora has long been known to have short 
anterior legs; that of Margarodes was quite unknown until 
lately described by M. Lataste in the Actes Soc. Scien. Chili, 
Vol. VII (1897), pp. 99-102. Lataste’s account, relating to 
M. vitium Giard, is quite full, and he gives a figure of one of 
the curious anterior legs with its thickened femur. Nobody, 
however, seems to have seen the insects digging until now, nor 
to have known the purpose of the peculiarity. 
The following description will serve for the identification of 
the New Mexico Margarodes: 
Margarodes hiemalis, sp. nov. 
Adult 9. Bright lemon yellow, very soft, oval; 5% mm. long, 4 broad, 
2% high ; segmentation distinct, each segment with a whorl of mostly black- 
ish but inconspicuous hairs; apex of abdomen with a small reddish hairy 
prominence ; abdomen on ventral surface longitudinally sulcate on each 
side, but the median area bulging, not depressed ; a deep median depression 
between the levels of the first two pairs of legs ; thoracic spiracles present 
as usual, but no abdominal spiracles noticed ; mouth parts entirely absent ; 
antenne short, moniliform, light reddish brown, except segments 1 to 3, 
which are pallid, 8-segmented ; segments 1 and 2 very short, ring-like, fully 
three times as broad as long, 2 smaller and not so broad as 1; 3 trans. 
versely oval, large; 4 very short and broad; the next 3 almost cordi- 
form ; the last (8th) spherical; sutures between segments 3 to 8 very deep ; 
8 with some long hairs at end ; skin minutely papillose ; a dull pinkish patch 
between the antennz ; legs present; first pair adapted for digging; femur 
excessively broad and short, forming a low rounded cone, on which is a 
shining red-brown rounded structure, divided by a suture in the middle; 
the basal part of this, which is the tibia, is broader than long; the apical 
part (tarsus) is continued at its apex into a stout long piceous process, 
which forms a digging claw. The other legs are similar in structure, but 
considerably smaller; the claws are all incrusted by a black substance, 
which on one of the middle legs forms quite a big lump. 
Adult ¢. Length of body about 2 mm., of abdominal brush: about 
