194 



PSYCHE. 



[December 1S91. 



remained, and the general look of the larvae 

 was like Tolype laricis except in color. 



The larvae moved very rapidly, and when 

 at rest lay closely adhering to the twig of 

 honey-locust, so flat as to be inconspicuous. 

 The cast skins seemed to be thicker and 

 more leathery than those of most Bombycid 

 larvae. These larvae drank less than most 

 that I have reared. 



Cocoon. Aug. 5. The first one spun athin 

 parchment-like cocoon, 3-4 of an inch long, 

 oval, slender, of a red-brown color mottled 

 with gray. It spun very slowly, taking over 

 two days. 



Pupa. Aug. 11. The pupa was formed. It 

 was 3-4 of an inch long, slender, dark brown, 

 and had a white chalky substance all over it, 

 which fell oft" when the pupa was touched. 



PREPARATORY STAGES OF PHEOSIA DIMIDIATA H.S. 



BY HARRISON G. DYAK. 



Pheosia dimidiata Herrich-Sch'Offer. 



1854 — Herr-Sch., Saml. ausser. schmett. , 



p. 66, fig. 515, Drymonia. 

 18S2 — Grote, New check list, p. 19, Phe- 

 osia. 

 rimosa Packard. 



1864 — Pack., Proc. ent. soc. Phil., v. 3, 



P- 358. 

 1877 — Lintner, Ent. cont., iv. p. 76 = dic- 



taea. 

 1878 — Tepper, Bull. Brook, ent. soc, 



v. 1, sp. dist. 

 1882 — Goodhue, Can. ent. v. 14, p. 73. 

 1890 — Packard, 5th rept. U. S. ent. coram., 



P- 455- S J>- dist. 

 1891 — Dy*ar, Psyche, v. 6, p. 128. 

 califomica Stretch. 



1873— Stretch, Zyg. & Bomb. N. A. v. 1, 

 p. 116, pi. 4, fig. 5, larva, pi. 10. Noto- 

 donta. 

 1S77 — Lintner, Ent. cont., iv. p. >j6, pr. 



sy/i . 

 Egg. Hemispherical, 'the base flat, smooth, 

 sublustrous, white. Under the microscope it 

 appears closely covered with dense, very 

 small, rounded granulations, which are of 

 about uniform size, but fused into a small 

 white spot at the micropyle. Diameter 1.1 



mm. Laid singly, usually on the under side 

 of the leaves of its food-plants. The larva 

 hatches by eating a hole in the side of the 

 egg, but leaves the rest of the shell intact. 



First stage. Head slightly bilobed, black 

 and shiny; labruni white; a few hairs; width 

 .6 mm. Joint 12 is slightly enlarged dor- 

 sally, otherwise the body is uniformly cylin- 

 drical. There is no trace of the caudal horn 

 so conspicuous in the last stage. Body pale 

 white; cervical shield, anal plate and tho- 

 racic feet black. From the minute elevated 

 dots arise blackish hairs which are appar- 

 ently not glandular but pointed at tip. A 

 subventral broken blackish band which later 

 changes to purple. Legs normal, the anal 

 pair not elevated, all black outwardly. Near 

 the end of the stage a purplish patch appears 

 under the skin on joint 12 dorsally in the 

 location of the piliferous dots of row 1, indi- 

 cating the origin of the caudal horn. The 

 piliferous dots of row 1 are close together on 

 joint 12, more normal on joint 11 and almost 

 in line with those of row 2 on the anterior 

 segments. Row 3 are large, lateral; rows 4 

 and 5 small ; row 6 distinguishable only on 

 the legless segments and row 7 normal, on 

 the venter of the apodal joints. In the latter 





