1.^ 



PSYCHE. 



[Febi-uacy iSgo, 



narrower: last segment also narrower and 

 bluntly rounded at the posterior extremity 

 Avith two very short, pointed tubercles. On 

 each segment i.s a transversely oblong, rugose, 

 corneous patch divided in the middle by a 

 narrow dorsal line. 



Length about [4 mm. Width about 

 4 mm. Lives in numbers in fungus found 

 on stumps anil decaying trees. 



William BenfcvwUllcr. 



Observation.? on Saturnia Io. — At 

 Lexington, Mass, 3 Jul^-. 1888 I found on 

 the upper side of a leaf of false indigo (^Bap- 

 tisia tinctoriii) a cluster of about fifty (50) 

 eggs. Shafe: oblong, compressed on two 

 sides. Attached to the leaf by their ends and 

 touching each other by their sides. Ar- 

 ranged for most part in rows. Color: white, 

 Avith black spots on outer end. In some the 

 compressed sides were white, while in others 

 they were partially yellow and in others still 

 there was a black spot on each side. On 4 July 

 I found on the underside of wild cherry {Prit- 

 nus scrofiiia') leaf a cluster of about thirty-four 

 (34) ^00^ '"^""^ these had hatched 6 July. 

 The young larvae were brown, with the head 

 much darker than the body. There were 

 four rows of spines, sending out star-shaped 

 clusters of concentric branches. 



As observed by all writers Who have de- 

 scribed these caterpillars, they have an odd 

 way of following each other, like a file of 

 soldiers, keeping their line of march un- 

 broken, even when turning corners. 



The first moult occured 13 July, the second 

 22 July. I have no record of subsequent 

 moults. 



On the 20 July I found another cluster of 

 thirty (30) eggs also on the under side of a 

 wild cherry leaf. These hatched 2 August. 



Again, 25 July, in the same situation I 

 obtained a cluster of twenty-three (23) eggs. 

 These hatched i August. 



From these various broods of larvae I 

 raised a large number of imagines, which 

 afforded me a good opportunity of studying 

 the typical and the variational forms. The 



following are my cot^ciusions; the males 

 differ from one another far less than do the 

 females. In the latter the typical form has 

 the foi'e wing plum-colored and the central 

 dark spot of the hind wings nearly equi- 

 distant from the surrounding dark circle. 

 From the plum-colored form there are several 

 gradations of shade, till we reach a variety in 

 which the fore wings are light brownish grey, 

 with but little of the typical plum color. 

 From the nearly equidistant spot of the hind 

 wings we pass tlirough gradations in which 

 the spot has lost much of its roundness and 

 become nearly contiguous with the circle, on 

 the side towards the outer angle of the wing, 

 till we reach a well marked variety in which 

 the spot is pear-shaped with the small end 

 turned towards the base of the wing, the large 

 end almost touching the outer cii-cle. 



While the inales present less difference, one 

 from another, there is yet a well marked 

 vai'iety corresponding to that of the female 

 just described. On comparison I find that 

 out of more than thirty (30) females there 

 are only four(4) with the pear shaped spot' 

 Avhile of twenty (20) males there are six(6) 

 with this peculiarity. 



Through the kindness of Dr. H. A. Hagen' 

 I have examined the specimens of 5. io in the 

 collection of the Museum of comparative 

 zoology, where I find a verv i"emarkable 

 variety in a male, captured, I believe, by 

 Dr. R. Thaxter at Newtonville, Mass., 27 

 June, 1870. 



In this specimen the anterior wings were 

 in the main typical; but the plum-colored 

 concentric spots were somewhat peculiar, the 

 outer ones becoming parallel lines instead of 

 spots. It was in the hind wings that the 

 aberration was most striking. The violet 

 centre of the dark spot was reduced in size, 

 and the surrounding dark area extended to 

 the circle with only a mere suggestion here 

 and there of the normal yellow belt between 

 the dark spot and the circle. The latter, in 

 its turn, had run over into the yellow belt 

 beyond thus niaking a highly suffused variety. 



It is mv desire at some future time to 

 ascertain whether these imaginal variations 

 correspond with any larval peculiarities, and 

 also whether they can be reproduced in 

 breeding. 



Ffo I in e s 1 1 in k ley . 



