40 



it was caused by a lack of water ; accordingly I wet a few leaves 

 and fed them to the larvae. Shortly after this they were taken with 

 a violent scouring, which so reduced them that all but one died ; 

 this one went on to a chrysalis, but died before producing the moth. 



On the 6tli of the following July, I obtained another laying of 

 eggs, and the larvae from these showed the same variation in size 

 as those of the first brood. When some of them became nearly full 

 grown they were attacked with a disease which caused them, in a 

 short time after death, to turn black; if handled the skin readily 

 broke, showing the interior to be filled with a blackish liquid. As 

 soon as the disease made its appearance, I removed the larvae to 

 new breeding cages, but without avail, as they all finally died of 

 this disease. 



In giving an account of these worms in the Canadian Entomolo- 

 gist* I referred them to precationis instead of the simplex. This was 

 owing to the fact that the moths from which I obtained eggs had 

 the silvery mark near the center of the fore-wings, nearly as they 

 are in a precationis moth which Prof. Grote determined for me a 

 few years ago. I have been able the present season to correct my 

 mistake by the use of the excellent description of these moths 

 which Prof. Thomas gave in his Fourth Eeport.t These descriptions 

 are as follows : 



''Plusia precationis, Guenee. The wings and thorax of a deep pur- 

 plish-brown color. The inner transverse line, which marks the 

 division between the basal and middle area, is formed by a slender 

 thread of golden scales, obliterated toward the costal margin, the 

 outer transverse line indicated by a narrow purplish shading, with 

 a strong forward bend opposite the outer metallic spot ; the fringe, 

 which is pale lilac, is preceded by a very slender pale inner, then 

 by an outer black marginal line, and is interspersed with black ; the 

 darkest pqrtions of the wings are the space around the metallic 

 spots and the interior portion of the outer area (considering the 

 wings as spread). The metallic spots have more of a golden hue 

 than those of the species heretofore described, they are also dis- 

 tinctly separated and prominent ; the outer or posterior, ovoid, the 

 the inner or anterior, when seen from the base of the wing, resem- 

 bles an interrogation point ('?), but seen from behind, when the 

 wings are spread, resembles an Italic v, the open part turning for- 

 ward and inward. The posterior wings dark uniform fuscous, with 

 a coppery luster. Underside dull ochreous, somewhat dusky ; the 

 posterior pair crossed by three fuscous lines, two of which are par- 

 tially visible on the anterior wings. The anterior part of the collar 

 a bright red. Expanse, 1.50 inches." 



"Plusia simplex, Guen. Front-wings with apical angle well de- 

 fined ; anal angle somewhat dentate ; general color grayish-brown ; 

 middle space behind the metallic spot dark brown ; the inner or 

 basal space, and anterior portion of the middle space, dark ash- 

 color, with a slight purplish tint, sprinkled with black points ; the 

 interior transverse line which separates the basal and middle areas, 

 a very oblique, straight, narrow, silvery line, which runs from the 



*VoI. XIII. No. 2. pages 21-23. 



tNinth Annual Report of the Stat'; Entomologist of Illinois, pages 47 and 48. 



