282 



PS TCHE. 



[ July, 1S92. 



decidedly nearer Euclea and other Coch- 

 liopodidsthan the Liparidae (I have ex- 

 amined the venation of Orgyia and 

 Parorgyia). Lagoa has the same wide 

 costal region of the fore wings as in 

 Euclea, that of the Liparidae being very 

 narrow ; the five hranches of the sub- 

 costal vein are thrown off in nearly the 

 same manner as those of Euclea and 

 Limacodes. The discal veins and ori- 

 gin of the independent (6th subcostal) 

 are almost precisely as in Euclea, and 

 the four branches of the median vein 

 are also similar in their mode of origin, 

 and unlike those of Orgyia and Paror- 

 gyia- 



In the hind wings, as in the Cochlio- 



podidae, there are ten veins, in the Lip- 

 aridae only nine ; there are but two 

 branches of the subcostal vein, the 

 third branch being detached, so that 

 there are two independent veins, one 

 arising from the anterior, and the other 

 from the posterior discal vein. In the 

 Liparidae mentioned there is no inde- 

 pendent vein. The four median vein- 

 lets have the same peculiarities in their 

 mode of origin as in Cochliopodids and 

 the same differences from the Liparidae. 

 To sum up : in the superficial char- 

 acters of the imago, and in having ab- 

 dominal legs in the larva, Lagoa resem- 

 bles the flat, scale-like Liparidae, but in 

 all its essential characters, those of the 

 ^gg, of the larva, pupa, and imago, it 

 belongs with the Cochliopodidae, except 

 in the matter of the presence of abdomi- 

 nal legs in the larva. On this account it 

 seems fairly entitled to be regarded as 



th^type of an independent group. We 

 may regard it as a generalized, ancient 

 group of Cochliopodidae, and refer it to 

 a subfamily Lagoinae, or we may boldly 

 remove it altogether from either of the 

 two families mentioned and consider 

 the genus as the representative of a dis- 

 tinct family and designate the group by 

 the name of Lagoidae. 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 a 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 Li- 

 parid ; 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 

 overwhelmingly Cochliopodid. Under 

 these circumstances we feel justified in 

 regarding Lagoa as a most interesting 

 ancestral form, and as affording argu- 

 ments for considering the Bombyces as 

 a whole as a generalized and ancestral 

 group, and as epitomizing the other 

 higher lepidopterous families. 



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 re- 

 spects it is intermediate between the 

 Saturniidae, especially the higher At- 

 tacinae and the Cochliopodidae. 



