94 REV. A. Miles moss on the 



the dorsal plate on segment 12 occurs a smaller mark, resembling the bent leg of 

 some animal, the angle pointing towards the anal aperture. All these strange- 

 shaped marks are of a bright lemon-yellow, dotted irregularly with a few fine grey 

 touches. The head is large and round, and in colour deep carmine. The dorsal 

 plate on segment 2, a similar plate on segment 12, forming the basal area of 

 the tail, the anal flap and claspers are all of an intense orange-vermilion, more or less 

 heavily spotted with minute black tubercles. A small additional plate of lighter hue 

 is situated above the anal flap, and is also sprinkled with black dots. Legs and 

 claspers of a more subdued red and ringed with black. The tail representing the 

 caudal horn, which is now only about half an inch in length, is altogether peculiar in 

 formation, being hardly more than a stout bristle bent abruptly backwards. Spiracles 

 black and consequently inconspicuous upon the prevailing black ground-colour. 



Pupa (PL XV. fig. j). — Rich mahogany-brown, very glossy and extremely active. 

 As already anticipated from the comparatively short proboscis of this large moth, there 

 is no free proboscis-sheath. The pupa is long and very gracefully curved, the last 

 abdominal segment terminating in a stout, sharp spike. The wing-cases are adorned 

 with black lines indicating the nervures, the dorsal area touclied with black, and the 

 abdominal segments transversely crossed by interrupted black lines. 



285. IsoG.XATiius swAixsoNi. (Plate VIII. /-».) 

 R. & J. p. 355. 



Gene7'al Distribution. — Surinam, southward to South Brazil ; Peru. 



Doubtless a common species in the Interior, but apparently not of a migratory 

 tendency, and limited in its range to the region of its food-plant, a wild Picus, 

 locally known as " caucho de monte." As a larva in all its stages it is one of the 

 most remarkable I have ever set eyes upon, and, though I several times found it, I 

 only once bred the moth from a pupa found spun up on a rock *. During my limited 

 experience of the species there was but little essential change in its several instars. 



When young, the head, plate on segment 2. anal flap, and all the claspers were 

 of strong ochre, and the white ground-colour inclined to faint emerald-green. In 

 the later instars these colours vanished and a general creamy white prevailed. In all 

 stages the larva is zebra-like, the interstices being strongly banded with velvety black. 

 The anal flap carries a couple of black tubercle points, and the caudal horn is 

 represented throughout its entire larval period by the most extraordinary long black 

 tail, gracefully curved, flexible, and delicate, which is waved to and fro with a vivacity 



* I have since been successful in rearing a closely allied species of Isognatlms in Par;!, figuring both the 

 larva and its ornate yellow and black pupa. This, as is probably the case with the pupaj of the entire genus, 

 bears a strong resemblance to Erinnyis in colour, form, and activity. A further peculiaritj', chaiacteristic of 

 both genera, is to be noted in the cocoon of stout silk intermingled with scraps, three specimens being 

 found spun up thus on a stump of wood several feet above the ground. 



