292 
the presence of abdominal legs in the larva. On this account it 
seems fairly entitled to be regarded as the type of an independent 
group. We may either regard it as a generalized, ancient group of 
Cochhopodidz, and refer it to a subfamily Zagoine, or we may , 
boldly remove it altogether from either of the two families men- 
tioned and consider the genus as the representative of a distinct 
family and designate the group by the name of Zagoide. This on 
the whole seems to us to be perhaps the most judicious course to 
pursue. At all events the insect is plainly enough an ancient, 
ancestral, or generalized form. It is, so to speak, a primitive 
Cochliopodid with larval abdominal legs. It lays eggs like those 
of Limacodes, etc.; its head in the larval state is concealed from 
above by the prothoracic hood ; its larval armature is more of the 
. Cochliopodid type than Liparid; so are the pupal characters and 
the nature of the cocoon; and the shape of the important parts of 
the head and the essential features of the venation are overwhelm- 
ingly Cochliopodid. Under these circumstances we feel justified in 
regarding Lagoa as a most interesting ancestral form, and as afford- 
ing arguments for considering the Bombyces asa whole as a general- 
ized and ancestral group, and epitomizing the other higher Lepidop- 
terous families somewhat as Marsupials do the placental orders of 
mammals. 
The genus is peculiar to North and South America, and may 
rank with such forms as the colossal sloths, and certain American 
vertebrate survivors of middle Tertiary times. In some respects it 
is intermediate between the Saturniide, especially the higher Atta- 
cine, and the Cochliopodide ; its clypeus, and the larva, approach 
in some respects those of the Attacine. 
[Nore. I find since this paper was read to the Society that, ac- 
cording to Berg (MfisceHlaneca Lepidopterologica, 1883), Megalopyge 
of Hiibner preoccupies Lagoa. Berg also founded the family 
Megalopygide, of which Lagoidz is a synonym. | 
