1890.] 
495 
[Packard. 
to the caterpillars having changed their environment from herbs 
to trees, and being subjected to the same conditions as the Bom- 
byces themselves . 1 
In the exclusively low-feeding caterpillars of certain groups of 
butterflies, the body is usually smooth, and adorned with lines and 
spots, while the genera] feeders and many arboreal forms are often 
variously spined and tuberculated, yet many spined caterpillars of 
butterflies feed on low herbs . 2 The Sphingidae in part feed on 
low plants and in part on trees, and they do not, except as regards 
the caudal horn, exemplify our thesis. 
Of the great group of Geometridae, many kinds are arboreal 
(Dendrogeometrids), and in such cases are almost invariably tu- 
berculated in manifold ways. We know of no hairy or tufted cat- 
erpillars of this group, or of any family below them, with the 
exception of the Pterophoridae. 
The arboreal Pyralidae, Tortricidae and Tineidae live in such 
1 It is hardly necessary for us to express our entire disagreement with the view of 
Mr. A. G. Butler, that these Noctuidae are really Notodontians, or in any way allied to 
them. It seems to us that the characters which he uses to remove them from the 
Noctuidae are superficial and adaptive. Nearly twenty-five years ago I satisfied my- 
self, after an examination of the denuded head and wings, that the Noctuo-bombyces 
were true Noctuidae, and did not depart essentially from the typical genera. 
2 While many, though not all butterfly larvae, as shown by Scudder and W. H. 
Edwards, have spine-like glandular hairs in the first stage, which may in some cases 
persist into one or two later stages, the body in many species, especially in those 
which are not general feeders, but select low-growing, herbaceous plants, becomes 
smooth and ornamented with stripes or spots. However, as a rule, butterfly larvae 
cannot be divided, as the Bombyces, etc., into highland low-feeders ;]yet, from Scudder’s 
“ Classified list of food plants of American butterflies ” (Psyche, 1889), the following 
facts and conclusions may be stated : 
Hesperidce.— Out of forty-five species enumerated all but six feed on herbs and especi- 
ally on grasses, and those which feed on tall shrubs or trees, such as Epargyreustityrus 
and five species of Thanaos, stand at the head of the group, which, as everybody 
knows, is the lowest family of butterflies, and nearest related to the moths. 
Papilionidce.— Of the six species enumerated, three feed on trees, as well as shrubs 
and herbs; one of these, however (P. cresphontes), feeds on trees alone. None of this 
family are hairy or spined when mature, except P.philenor, with its peculiar flexible, 
spike-like growths. 
Pierince.— Of ten species, all feed on herbs, rarely on low shrubs, and none are 
armed with hairs, bristles or spines. The other two groups {Lyccenidce and Nympha- 
lidcB ) are general feeders, occurring indifferently on herbs, vines and trees, except the 
striking case of the eight Satyrinae, which feed exclusively on grasses and herbs ( E . 
portlandia, however, sometimes frequenting the Celtis). The very spii>y Argynnis lar- 
vae feed on Viola. It should also be noted that many moths, Notodontians among 
them, which in the northern states feed on trees alone, in the Gulf states, according to 
Abbott, feed on shrubs, vines and low plants, as well as trees. 
In reply to an inquiry, Mr. W. H. Edwards kindly writes me : “I do not think that 
the butterfly larvae which live on trees are under more favorable conditions than low- 
feeders, as to healthiness, or ease of rearing.” 
