2(52 MEMOIUS OF THE NATIONAL ACADEMY OF SCIENCES. 



Oroiio, Me. (.Mrs. Fcrnald); I>niiis\vi<'k. :Me. (Packard); Lawri'iioe, Mass. (Mr. Treat, Mus. 

 Comi). Zool.i; Pnivideni-e, K. I. (Packard); New York (Dyar, ITulst); Plattsburg, N. Y. (Hudson); 

 Peuiisylvaida ((irotc, Amer. Eut. Soc); New Jersey, Pcuusylvaiiia (Palm); (ieorgia (Leconte); 

 JMarylaud (Mus. Comp. Zool). Larva fouud on Indiau Itiver opposite Micco, Fla. (Prof. J. \V. P. 

 Jenks). 



Siiht'aiiiily Ceuurin.t;. 



Head broad and full; auteuuic with loug, close pectinations in both sexes, in S the branches 

 being- unusually long. Labial palpi reduced, three-jointed, the third an<l other joints when 

 denuded not being distinct, while the scales are slender and sparse compared with those ot other 

 Notodontians. Fore wings moderately long and narrow, the outer edge either quite oblique or 

 moderately so. Hind wings generally produced. Abdomen often broad and very hairy at the end 

 in S . Color, wliite or pale asb, with brown-black transverse lines, sometimes eight in number; 

 a discal ringlet; tliorax and abdomen transversely striped. 



Cocoon very dense, oval, flattened, the edges broad and thin: well rounded above. Often 

 covered with bits of bark and wood. Attached to the bark of trees. 



Pupa cylindrical, a little flattened beneath; rounded at each end; with no cremaster. 



Larva with abroad i)rothoracic segment, in which the head is partially retractile, and bearing 

 a pair of lateral tubercles. Anal legs converted into long slender fllamental legs (stemapoda), 

 each ending in an eversible flagellum. Young larva with a pair of long, hornlike prothoracic 

 tubercles, and the stemapods a little longer than the body. 



The following account of the Tuode of emergence of the Cernras from tlicir cocoons, by 

 Dr. T. A. Chapman, will prove interesting: 



Some pupil; are able to turu arouud iu their cocoons, but I think the majority have their backs to the tree and 

 their fronts to tlie exposed portion of the cocoon, and are practically fixed iu their position. Tlien all the cocoons 

 I have examined (thirty or forty) have .i decidedly thinner- place over the front of the head; it is larger than the 

 cross section of the pupa; it contains fewer chips, and, held against the light, is (juite translucent, while the rest 

 of the cocoon is o])a(iue. This is the portion of cocoou that is operated on for emergence. 



I stated (loc. cit.) that the pujiic of onr Cernras were fairly rounded in front; in this I was decidedly iu error, 

 for liiiiila has nearly as pronounced a keel on the head .as ('. mulliscr'nila, to which 1 referred. Onr " kittens'' arc 

 niucli smoother, though the same structure is indicated. It was observing this structure of riiiula that tempted me 

 to try to make further observations. I made a detailed description of this portion of the ])upa of riiiula. but I 

 may omit it, as I made no observations that conuectcd any habit with any i)eculiarity of this portion of the i)Upa'. 



The dehiscence of the pupa consists in the thorax splitting dorsally and the division, proceeding to either side, 

 separating the wings from the first three abdomiual segments; the antennae cases sometimes adhere to the wings, 

 sometimes are separate; the leg and mouth-p.art coverings form a separate piece, whose apex tends to adhere to 

 wings and abdomen. But the head covering, consisting of the ridge (or keel) and hollow on either side of it, the 

 eye covers (including the gl.azed side portion), the face down to a certain incision, ami a small portion below which 

 is probably the labnim, separates as a distinct portion during the whole period of emergence and until the head 

 is <iuite clear of the cocoon and often even after the moth has completely escaped, and is always fonml outside the 

 cocoon. During this period the rudimentary pro])oscis is very visible as two short white papilla', free from any 

 hairs, and it is .just above the base of tlieso tliat the softening lluid exudes. This llnid is stated to l)e acid; this I 

 did not test, but I ibnnd it to be colorless and tasteless, aud it evaporated without residue; applied to the material 

 of cocoon it softened it, but not at all rapidly. The moth nnikes many rotatory movements after the splitting of 

 tlie jiup.a case, no dcmbt in order to smear his fluid over the necessary area of the cocoon, aud we here see how 

 little further is wanted to reach a haljit similar to that of milliauseri, especially as the smearing process and delay 

 for softening takes a considerable time, probably more than five minutes, possibly half an hour. This appears also 

 from the amount of tlntf rubbed about inside the cocoou in many cases. The moth keeps quite dry, and the head 

 cover is dry outside, but moist within, when removed from the newly emerged moth; its function appears to be to 

 protect the front of the moth during the movements of smearing and as a strong medium for applying the final 

 breaking force to the cocoon. This use of this portion of the pupa case is by no means confined to C'ernra, but is 

 connuon to many moths that have to break through cocoons or out of the ground. It has, however, nothing to do 

 witli the actual distril)Ution of the fluid, so far as my observations were decisive. I made one other observation 

 that added a new point to l)e exi>lained, viz, tliat when the moth emerged it often brought with it pieces of very 

 delicate tissue that I passed over at first as being portions of the inner divisions of the jiupacase; they proved, 

 however, to bo bits of tlie inner lining of the cocoon. The wall of a sound cocoon appears to bo homogeneous; but 

 in a cocoou where 1 stopped the moth before breaking it open, but alter softening, this inner layer of very line 

 membrane is (juito visible. I could not help fiaming several theories as to this, but as I know no more thau I have 

 stated, the theories may for the present remain iu abeyance. .^Entomologist, xxv, pp. S02-304, Dec, ISDL'. London.) 



