866 
PSEUDOSPHINX; ISOGNATUS. By Dr. M. DRAUDT. 
tetrio. 
obscura. 
leachi. 
swainsoni. 
scyron. 
menechus. 
rimosa. 
them. Head two-pointed triangular, horn long, feebly curved. It lives on Juglans, Ostrya. Canada to Florida 
and Texas, to the west as far as the Mississippi. 
B. Sphingidae semanophorae (with a scent-patch inside on the basal joint of the palpus). 
Subfamily: Sesiinae. 
1. Tribe: Dilophonoticae. 
27. Genus: Pseudospliiiix Burm. 
Scarcely separable from the following genus in structure, but of a very different exterior; hair-tuft 
on mesothorax somewhat higher, but more sharply interrupted posteriorly, the whole metathorax shorter. 
Only 1 species: 
P. tetrio L. (= plumeriae F., hasdrubal Cr., asdrubal Poey, rustica Sepp.) (98 a). One of the com¬ 
monest Sphingidae with most gigantic females, the q darker than the $, whitish-grey, with brown, very ir¬ 
regular linear markings, the S with a brown basal spot at the costal margin and a brownish area behind and 
below the cell, a strong black discal streak and a black streak terminating into the distal margin far below 
the apex. Hindwing blackish-brown, whitish-grey at the anal angle with dentate lines therein. Intensely 
darkened blackish-brown S<S belong to — obscura Btlr. — Larva of a very striking colouring, black, with 
yellow segments, red head, feet and anal segment, and a long thread-like horn; it lives gregariously on Euphor- 
biaceae and Apocyneae, especially on Plumeria. According to observations by Miles Moss it seems to remain 
unmolested by parasites, whereas v. Bonningh ausen states it to be much stung by parasitic flies. The 
pupae are found covered in leaves that have dropped to the ground and have been spun together with few silky 
threads. Very widely distributed from Florida across the West Indies, to the south as far as Paraguay and 
South Brazil. 
28. Genus: Xsoguatlms Fldr. 
Of almost the very same structure as Pseudosphinx and Erinnyis ; strongly built, thorax with a low 
tuft. Margin of forewing slightly undulate-dentate, hindwing yellow. Several similar species. 
Type: I. scyron Stoll. 
I. leachi Sivains. (= cahuchu Bsd., metascyron Btlr., scyron Wkr. part., pedilanthi Bonningh.) (95 d). 
Dark wood-coloured brown, mixed with grey and black, slightly strewn with greyish-white, a dark basal 
spot is about 2% mm broad; cross-vein light, a dark cellular spot before it, another round spot behind it, 
the black streak between 3 and 4 is very thick, more or less connected with a curved spot above 2; without 
grey vein-streaks in the postmedian area. Hindwing ochreous as in all the species, with a regularly dentate 
marginal band. Abdomen unicoloured. Larva — at least probably — brownish-black and with grey spots, 
with a filiform caudal horn and a red head; on Plumeria. Surinam to Southern Brazil. 
1. swainsoni Fldr. (= fumosa Btlr., scyron Wkr. part., pedilanthi Bonningh. part., zebra Clark) differs 
from leachi in the increased white irroration and interrupted whitish-grey vein-streaks in the postdiscal area; 
the two spots in and behind the cell-apex are confluent, the basal spot is narrower, and the space between 
veins 2 and 3 less dark brown; marginal spots at the ends of the veins larger and lighter grey. The mar¬ 
ginal band on the hindwing is broader and only very little inwardly dentate, or not dentate at all. Surinam 
to Southern Brazil. Larva black, with white segments and red head, anus and abdominal legs, the filiform 
horn enormously long. It lives on Plumeria. 
I. scyron Stoll (= pedilanthi Bsd.) (95 e) has a distinctly banded abdomen, ground-colour more red- 
brown, ventral side dingy reddish-white. Postdiscal area of forewing with a grey vein-stripe interrupted by 
black dots; disc of S with 2 black spots in a reddish area between 4 and 2, absent in the $. Venezuela to Para, 
Trinidad. 
I. menechus Men. (— amazonicus Btlr., pelops Bsd., rimosa Bsd., scyron Wkr. part.) (95 f). Well 
characterized by the peculiar bluish-grey ground-colour, very strongly built body and distinctly banded 
abdomen; forewing with double antemedian and discal transverse lines which are more distinct at the costal 
margin, interrupted on 5, concave below it and connected with the antemedian pair, so that a half-ring is 
produced, which is open towards the inner margin. Larva similar to that of Ps. tetrio, with white segments, 
orange-red head, abdominal legs and anal segment; according to Miles Moss the segments are not white, 
but spotted red. On Artocarpus. Surinam to Espiritu Santo. 
I. rimosa Grt. (95 e). Forewing and thorax chalky greyish-white, abdomen with distinct bands. Fore¬ 
wing with large white marginal spots. Hindwing lighter yellow. The species is most variable and divided into 
many subspecies. The collar of the nomenclatural type is not striped brown, the black basal spot of the 
