18 PROCEEDINGS OF THE NATIONAL MUSEUM. VOL, 62. 
An attempt to indicate these is made in the following key to the species 
of the genus: 
a!, Derm with specialized, usually lanceolate or cylindrical spines; derm disk pores 
of two sorts only. 
b', Disk pores of two sorts, smaller trilocular, and large multilocular with oval 
to quadrilocular centers; specialized spines stout lanceolate, apparently 
scattered; antennae 7-segmented; size small (about 6 mm.). 
fuscus Maskell.® 
b?, Disk pores mostly multilocular with large trilocular centers, smaller dorsally, 
larger ventrally, rarely, in genital region, with oval centers, trilocular tubu- 
lar pores, occurring only at and near body margin; with clusters of small, 
slender, cylindrical to somewhat lanceolate specialized spines along body 
margin, especially in abdominal region; ventral cicatrices in single irregu- 
lar rows; antennae 8-9-segmented; size larger, 8-14 mm, 
crawfordi (Maskell). 
a?, Specialized spines wanting, only the long slender conical sort present; ventrally 
and at margin with large tubular multilocular disk pores with circular centers, 
not found in preceding species, making three sorts of disk pores. 
c!. Dorsal disk pores not appearing multilocular, but tri- or quadrilocular; derm 
spines crowded and abundant, tibia and tarsus with heavy spines; large 
tubular trilocular pores present; derm only slightly chitinized at maturity; 
size smaller, length not over 16 mm.; living on the trunks or branches of 
the host. 
d'. Dorsal disk pores normally with quadrilocular centers; derm spines large 
and closely crowded, distinctly more abundant than pores; dorsal and 
ventral spines in middle region of body averaging approximately the 
same length; ventral cicatrices in single pu el row; antennae 8-9- 
sepmentied CLL IO YO Ue ee. opllosior (Maskell) 
d, Dorsal disk one meatal ey with trilocular eae oder spines not so 
numerous, not distinctly more numerous than pores; dorsal spines in 
middle region of body averaging much smaller than ventral in same re- 
gion; the ratio approximately 6 to 10; ventral cicatrices more numerous, 
in transverse bands several pores wide; antennae 7-segmented. 
comperei, new species. 
c?, Dorsal disk pores multilocular, with triangular or quadrangular centers; derm 
spines comparatively few, widely separated; tibia and tarsus with the 
spines longer and more slender; large trilocular tubular pores apparently 
wanting; derm relatively heavily chitinized at maturity; size large, 20-22 
mm.; ventral body spines slightly longer than dorsal; abdominal cicatri- 
ces in single irregular rows; antennae 9-segmented; living on the roots of 
theshost s. Lacs. .u esck Se iecuca. Gelil.ueawe ll. Subterraneus, new species: 
The larva of M. fuscus offers two definite characters which differ- 
entiate it from those of crawfordi and pilosior. ‘These are the pres- 
ence of thirteen instead of fourteen pairs of large, trilocular, tubular 
marginal pores, and the presence of a relatively decidedly shorter 
and stouter third antennal segment. No distinguishing characters 
have been observed between larvae of erawfordi “and pilosior in the 
limited material available for examination. 
Regarding Maskell’s various comments on these species, particular 
mention may be mude of his use of the presence or absence of a 
5 Included after the study of only a small portion of one specimen. 
