300 CALIFORNIA ACADEMY OF SCIENCES [Proc. 47H Serr. 
When compared with robustus, this species is found to be 
particularly distinguishable by its larger size, much broader 
interocular space and vertex, tegmina with greatest width meso- 
distad and separated by a space nearly equalling the tegminal 
width, and strikingly shorter and heavier caudal femora, which 
about reach the abdominal apex in males and fail to reach that 
point in females. 
Type: female, No. 717, Mus. Cal. Acad. Sci, Wenman 
Island, Galapagos Islands; collected late September, 1906, by 
F. X. Williams. 
Size large and form moderately robust for the genus. Vertex broad, 
interocular space broad (1. mm. in width). Fastigio-facial angle blunt, 
forming an angle of approximately 90°. Pronotum with dorsal portion 
of prozona and mesozona swollen, transverse sulcus weak but distinct, 
medio-longitudinal carina weakly indicated on prozona and mesozona, well 
developed on metazona, caudal margin or disk broadly convex with a 
very small median angulate emargination. Disk of pronotum scarcely 
pitted, almost smooth, in prozonal and mesozonal portion, rugose on meta- 
zona, this surface less rough than in robustus. Tegmina decidedly shorter 
than pronotum, elongate-ovate, slightly wider meso-distad than proximad, 
with apices broadly rounded. Tegmina separated by a distance nearly 
equalling the width of one of the tegmina. Prosternal spine proportion- 
ately small, conical. Ovipositor valves with apices moderately curved, 
intermediate in degree between the types shown by H. robustus robustus 
Scudder and H. robustus choristopterus Snodgrass, their internal surfaces 
similarly plentifully supplied, with rather short, silky hairs. Caudal femora 
heavy, much heavier and proportionately shorter than in robustus, not 
reaching the apex of the abdomen. 
Allotype: Male, No. 718. Mus. Cal. Acad. Sci., Wenman 
Island, Galapagos Archipelago; collected late in September, 
1906, by F. X. Williams. 
Size larger and form more robust, as compared with males of robustus. 
Vertex broader and blunter. Pronotum heavier, with dorsal portion of 
prozona and mesozona moderately swollen, transverse sulcus weak but 
distinct, medio-longitudinal carina percurrent, well developed, low but 
heavy and comparatively broadly rounded in transverse section, caudal 
margin of disk broadly convex with a minute median angulate emargina- 
tion. Disk of pronotum, tegmina” and prosternal spine as described for 
the female sex. Furcula represented by very briefly produced, transverse 
projections, with distal margins rounded but indicating some angulation. 
Supra-anal plate with lateral margins rather strongly convex-convergent 
proximad for a brief distance to above cerci and in this portion sharply 
but narrowly reflexed, thence straight and weakly convergent to distal 
portion, where they are very strongly convergent and weakly concave to 
the bluntly rounded apex, so that the distal portion of the plate is almost 
subtruncate. Surface of supra-anal plate showing a short medio-longi- 
tudinal sulcus in proximal portion, bounded by carine. Cerci heavy, 
hardly twice as long as proximal width, tapering very weakly to distal 
— 
11 The tegmina, though varying greatly in proportionate length to width, are seen 
in the series to be always much shorter than the pronotum and separated by a decided 
interval. 
