GOO On Synthetic Types in Insects. 



cylindrical. There is a general similarity in the terminal 

 segments of both insects and the female genital pieces. 



The thin squamation, the nocturnal habits, the stupid, 

 awkward, insensate flight of Hepialus, — that of Gorgopis 

 I have never seen, — remind us further of the hairy, thin- 

 winged, nocturnal Polystaechotes ptinctatus, which any light 

 attracts after nightfall in the woods of the colder portions 

 of New England. 



The Phryg-anidce as larvae are like the Psychidce which 

 live in cylindrical cases ; and there is between the imag- 

 ines of many species such a likeness that Newman has 

 placed Psyche among the Phryganids. 



There is also an interesting analogy that the larva of 

 Perla bears to the active larva of Meloe. Placing the 

 two side by side, we see that both possess a head whose 

 form is broadly triangular, the corners being rounded 

 oil". In the three rings of the thorax, which in both 

 larvae are equal in size and convex on the sides, while 

 the abdominal rings are contracted in length, and 

 slowly taper towards the long setae which adorn the ter- 

 minal segments of both insects, and in the closely ap- 

 pressed legs, which are stout and broad, the swollen 

 femora, and the long-clawed tarsi, there are characters 

 which aid in effecting this analogy of Perla to a coleop- 

 terous insect. 



The Psocidcs find their analogues in the Hemiptera. 

 The species of Psocus are so much like the Aphidoe that 

 when flying they are often mistaken for each other. And 

 indeed in the short broad body and broad head and long 

 antennce, in the very unequal wings, which are folded roof- 

 like over the short abdomen, in their simple ncuration, in 

 the short legs, and feeble tarsi, and their mode of flight 

 and appearing winged towards the close of summer, these 

 small insects are remarkably like the winged plant-lice. 



The species of Alropos, (commonly called book-lice,) 



