MEMOIES OF THE NATIONAL ACADEMY OF SCIENCES. Ill 



Efiy. — Liiid in iiregular patches of about 7o on the uiuleiside of ;; k\Tf; oval cylindrical, 

 larger at the lower end by whicli they are attached, bulging out a little above the base, and 

 contracting toward the top, which is somewhat crater-like; the inicropyle dark, distinct, and 

 situated at the bottom of a saucer-like depression; outside and below the rim of this crater is 

 usually (not always) an irregular crenulated edge or rim, which is partly eaten away by the larva, 

 in escaping from the egg. The shell is smooth, polished, not pitte<l when examined by a strong 

 lens, nulk- white, and resembling cheap white earthenware pottery. Under a h inch A eyepiece 

 the shell is seen to be ornamented with fine polygonal areas, but those of the lower part of the egg 

 are not distinctly six sided, being less regular and distinct than in the egg of I>. palmii. Diameter 

 about two-thirds mm., being considerably less than the height. 



Larva. — The specimens here described were received under the above name from Mr. James 

 Angus, September 4. I failed to note their length, but they were nearly, if not quite, full-grown. 



Head black, including the mouth-parts. The prothoracic shield is distinct, transversely 

 oblong, black. Bodj' black, with four narrow, pale whitish yellow stripes on each side. The two 

 dorsal stripes are wide apart, leaving a broad dorsal median black stripe; the space between the 

 first and second line is a little wider than between the second and third; the fourth line is 

 slightly wider than the others, scalloped, and interrupted by the sutures between the segmeijts. 

 Beneath the lateral ridge along the base of the legs is an irregular livid purplish stripe beginning 

 on the third thoracic segment. There are no hairs along -the back, and those along the side are 

 unusually short and are pale grayish in color. The body beneath is black, with a median livid 

 pinkish line along the abdominal segments, widening between the abdominal legs, and ending on 

 the seventh segment, the end of the body, including the anal legs, being black. 



The following account of its transformations is copied from Beuteumiiller: 



Egg. — Simil.ir ti.> that of I), ministra; can not be clistinguished i'roni it. Laid in masses on the underside of leaf. 



Touiig larra after first and seroiiil molts. — Can not be distinguished from those of D. inhiistra. 



After third molt. — Little change except in size. The stripes are now coutlueut about the .anal segments. 

 Length, 30 mm. 



After fourth molt. — Head jet-black, cervical shield now chestnut brown instead of black; otherwise as m 

 D. ministra. Length, 40 mm. 



Mature larva. — Head jet-bl.ack, shining, slightly punctured; cervical shield and neck wholly golden-yellow. 

 Body black, with four equidistant, stripes of citron-yellow on each side and three ou the nuderside. Abdominal 

 legs and bases of thoracic feet orange. The stripes all become conjoined at the posterior extremity. The anal plate 

 jet-black, very shiny and nearly smooth, and not roughly punctured, as in /*. ministra. The hairs over the body .are 

 sordid white. Length, 55 mm. .Single brooded. 



Mr. Beutenmiiller writes me that '"the young larva of 1>. atKju-'iii is different in coloration 

 from all the other known species. Tlie first and third thoracic segments are wine colored, as are 

 also the dorsal region of the fourth, tiftli, and seventh alidominal segments, and the body is 

 greenisli brown, provided with the usual number of yellow longitudinal stripes."' 



Habits. — At Salem, Mass., I found (August 26) 14 full-grown larvte and 40 others in the fourth 

 stage; early in the morning of August 28 these had molted and begun to feed. Larva in July and 

 August; moths April to July, District of Columbia and Maryland (Kiley). 



Pupa. — Body rather stout, surface very coarsely punctured, the pits more or less confluent, 

 especially on the thorax; head prominent, deeply notched at the end, and with two prominent 

 parallel ridges in front, with a deep valley between. The four terminal spines of the cremaster 

 equal in length and shape. On each side of the common base is a conical projection. Length, 

 15 mm (Figs. 50, 57). 



Food plants. — Hickory {Cari/a) and walnut (Ji(ijlait.s) Beutenmiiller; linden (Packard). In 

 Manhattan, Ivans., Betula (I'openoe), black walnut and hickory (Eilcy). 



Geographical distribution. — Brookline, Mass. (Shurtlefl' Mus. Bost. Soc. Nat. Hist.); Jamaica 

 Plain, Mass. (Jack, Mus. Comp. Zool.); Beverly, Mass. (Burgess, Bost. Soc. Nat. Hist.); 

 Plattsburg, N. Y. (Hudson); Chicago, 111. (Bolter); Illinois, Pennsylvania (Strecker); Auburn, 

 Jle. (Mrs. Fernald); Salem, Mass. (Packard); West Farms, X. Y. (Angus); Missouri and District 

 of Columbia (17. S. Nat. Mus.); New York, New Jersey, Pennsylvania, Arkansas (Palm); Ames, 

 Iowa (H. Osborn); Canada, Rhode Island, New York, Wisconsin, West Virginia, Indiana,. 

 Carboudale, 111. (French). 



