MEMOIRS OF THE JfATIOXAL ACADEMY OF SCIEXCES. 



145 



Pupa. — Eoily stout and tliick, not tapering mucli to tlie end. Surface of the abdominal 

 sesnients moderately punctured, tbe two last segments quite smootli. The cremaster ends in a 

 conical stout spine, broad at the base and sharp at the end, the point terminating in an unusual 

 Uiiid of armature which, seen from above or beneath, consists pf four laterally radiating, slightly 

 ui)turned, stout spinules, the lower ones considerably smaller than the distal ones. Length, 

 L>2-23 mm. 



Habits. — The caterpillar is most commonly found on the oak. Dr. Harris found it on the 

 oak, the moth occurring June 20. By the middle or last of September, in New England (Maine 

 and liliode Island), it begins to pupate, not spinning a cocoon, and jirobably entering the ground 

 before assuming the chrysalis state. In Providence it occurred on the white oalc, in Maine on the 

 red oak. In Georgia, according to Smith and Abbot, it ''feeds on the chestnut oak and other 

 oaks. It went into the ground October 10 and came out March 1.3. Another went in June 1 and 

 came out the lOtli of the same month." It is theiefore double-brooded in the Gulf States and 

 single brooded in the North. The following notes ou 

 its habits have been given us by Professor Riley: 



A ]iaii' of this moth were taken May 2, 1882, from the eggs 

 of whicli larra' hatched on the 9th. They went through tlieir 

 first molt May 15; second, May 22; third, May 20, and fourth, 

 May 31. Pupated June 12 to 14. The moths issued from ,Tuue 

 26 to ,TuIy 10. Several larvie of tliis moth were found by beat- 

 ing ou oak .lune 2H and July 10. 18S2. The larvie are now Tery 

 plentiful and of all sizes, on several oaks. (5th Rep. U. S. 

 Ent. Comiu.) 



Food pJanU. — Oak (Quercusof different species), 

 maple (Lintner), maple, white birch, sugar filum 

 (Dyar). (The statement in my Forest Insects, p. 4:14, 

 that Mr. Eeed had found it on the maple, is an error.) 



Gi'oiirnphical (li.sirihntion. — Eanges from Maine 

 and Canada northward to Oregon and Califorida, 

 occurring southward on the Atlantic and Gulf coasts to Florida, Georgia, and Texas. 



Amherst, Mass. (^Irs. Fernald). I have a S collected June 21 on the Vermejo Eiver, 

 northeastern New Mexico, by Lieut. AV. L. Carpenter, of the Wheeler survey. Plattsburg, N. Y. 



Fig. 0:i.— Pupa of Xadata gibbosa. 



marked success. A series calculated with the ratio 0..55 would give 0.41, 0.75, 1.27, 2. ,30, 4.3, and one with the ratio 

 0.73 or thereabout would interitolato a term between each one and give 0.41, 0..55, 0.7.5, 0.96, 1.27, 1.7, 2.3, 3.15, 4.3. 

 Thus it might be ctmsidered either that the species normally had eight stages (r.atio, 0.73) and omitted the second and 

 fourtli normal stages, or that it had normally live stages (ratio, 0.55); but interpolated a stage between the third and 

 fourth normal stages, and reduced the measurement in the last stage to correspond with the ratio between those 

 that immediately preceded it. The latter seems the more probable, but the fact is that the growth of the head at 

 the first and second molts is double wliat it is at the third, fourth, and fifth. It is a curious case. 



Xadata oregoiiensis Butler. 



This was described as a variety of X douhledayi Pack.; but Mr. Butler writes me under date of June 30, 1892: 

 "The types « » * have pale creamy bulf-colored palpi; quite uniform in tint * * » if there is a brown line 

 above it must be on the second joint, but I do not think there is one « ' • looliing at the moth without a lens 

 you would say the fringe was dark ferruginous ou primaries « • • and white tipped ou interspaces." , These 

 are the characters used to separate X. gibbosa from D. doubhdagi in Dr. Packard's description, and Mr. Butler's words 

 show that his form is not a variety of X doubledai/i, but the same as Hy. Edwards's X. behrensii. 

 1881— Butler, Ann. and Mag. Nat. Hist., p. 317. 

 bihrensii Hy. Edwards. 

 188.5— Hy. Edw., Ent. Amer., i, 49. 

 Eijij. — Rather more than hemispherical, the base flattened; smooth, not shiny, white with a yellowish tiuge; 

 diameter, 1.2 mm. I'nder a microscope the surface is seen to be covered with very slight, obscure, rouuded depres- 

 sions, Iiut, is in fact, almost smooth. 



Laid singly on the underside of the leaves of its food plants in early summer. 



Normal Stage I (first larval stage). — Head slightly bilobed, rounded, shining pale greeuish with a (e-K hairs; 

 mouth brownish, ocelli black; width, 0.75 mm. Body .slender, no tubercles or humps: feet normal, smooth, shiny, 

 pale yellowish green. Setit minnte, rather long but not evident, color blackish. As the stage advances great 

 S. Mis. 50 10 



