MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 23 



liaps dai)i;er sijiiials — tlioiij;li lator in life tlie brown shades and jjToeii tints, so like the green leaf 

 ■with its sorrated, blotched, serepatelied edj;es. would often deceive the most observant of birds. 



In regard to the nutant or movable tubercles, it may be ob.served that a slight motion 

 of these api)endages may suttice to scare off an approaching ichneumon or Tachina. If most 

 insects have, as supposed by Exner and by Tlateau, more imperfect vision than has formerly been 

 attributed to them, so that they are extremely nearsighted and oidy clearly perceive bodies when 

 in motion, then even slight movements of these tubercles, while the caterpillar itself was immobile, 

 would i)robably be sufticient to frighten a parasitic insect and deter it from laying its eggs on the 

 caterpillar. 



groupinct of notodontian larv.k according to their affinities and also their 



adaptation to arboreal life. 



As is well known, the larvae of this family vary greatly in form and ornamentation for a group 

 of such moderate numbers; and the following synopsis has been prei)are(l in order to show this 

 .^eat variety in as graphic a manner as possible: 



1. Body smooth, not hairy, witli red and yellow spots. Gluphinia. 



2. Body smooth, moderately hairy. Datana. 



3. Very hairy, the body almost totally concealed. Aimtclodes. 



4. Body smooth, hairless; with no humps or tubercles, of a noctuid shape; anal legs never 

 elevated; color green, with yellow lines, the latter sometimes edged with reddish; feeding less 

 conspicuously than any others of the family. Kadata, Lopliodonta, etc. 



r>. Body with two dorsal tubercles; also hairy. Ichihyura. 



G. Body smooth, polished; a single hump, surmounted by a horn on the eighth abdominal 

 segment. I'hcosla. 



7. Back 2-8-humped, serrate, body smooth, not brightly striped. Notodonta, Kerice. 



8. Body smooth, gayly strijjed, eighth abdominal segment gibbous. Edema, Dasylophia. 



9. Body smooth, with nutant tubercles on first and eighth abdominal segments; end of body 

 "uplifted. Colors green with brown patches simulating dead blotches on leaves. Hyparpax, 

 Schizxra, and XyJinodes. 



10. Body with stout spines and with spiny tubercles on first and eighth abdominal segments. 

 ■Schizura unicornis. 



11. Body smooth, tapering; anal legs normal, often with two jjrothoracic tubercles, enormous 

 in early stages. Hetcrocampa (juitlritta, biundala, and ohliqnn. 



12. Body smooth, striped; anal legs normal. Hetcrocaiiipn maiiteo. 



13. Body with two dorsal prothoracie tubercles; anal legs tilamental; each ending in an 

 ■eversiblc tlagellum. Macntrocampa marthesia. 



14. Body with two lateral prothoracie tubercles; anal legs filamental, each ending in an 

 •eversible tlagellum. Ceriira. 



15. Body doubly humped on the abdominal segments; filamental anal legs. The Old World 

 genus Staurojynn. 



So far as I have gone in the examination of the structure of the moths, this succession of 

 genera roughly corresponds with the classification of the family. Judging by the moths alone. 

 Dataim stands at one end of the series and Cerura at the other. 



Perhaiis Cerura has generally been placed at the end of the group because of its fancied 

 resemblance to the larva of Drepana, but this is deceptive, because the long caudal filament of 

 the latter genus is simply a hypertrophy of the suranal plate, and the anal legs themselves are 

 atrophied, while in Cerura they are enormously hypertrophied, probably owing to their active use 

 as deterrent appendages. 



SUMilARY. 



One would suppose that the two genera Nadata and Lophodonta, with the Old World genera 

 Pterostoma, Ptilophora, Drymonia, Microdonta, and Lophopteryx ' (of the two species L. cticuUina, 

 ■which is humped on the eighth abdominal segment, connects with the plain-bodied L. carmelita 



'The first larval stapes of the Collowiug genera are still imkuown. .and the author -n-ould he much iiulehted for 

 •eggs or aleoholic specimens of the larva; of the first and later stages: Kllida, Lophodonta, Drymonia, Notoilonta, 



