SPILOSOMA ACREA. 



Plate III. fig. '2. $.3. ^. 



Order: Lppidoptcra. Section: Noctuvna. Family: ArctMo!, Steph. 



Genus. Spilosoma, Stephens. Arctia p. Scltraiik. EJ^)r(•pia p. Oehsenheivi. Bombyx p. Fabr. 



Spilosoma Acrea. Alls niveis(postieis ^ fulvis), piinctisnigris, costalibus majoribus ; abilominis dorso fulvo nigro 



maculato. (Expans. Alar. $ 2 unc. — J -JJ unc ) 

 Syn. $ PhaXsena (Bombyx) Acrea, Drury, App.v. '2. 



$ . Phal. (Bomb.) Caprotina, Drury, App. v. 2. 



Bombyx Acria, Fab. Ent. Si/st. 111. l.p. 451. No. 137. Abbot and Smith, Ins. Georg. tab. G7. (exclus. Syn. 

 Fabr. B. luhricepitlse). 



Arctia Pseuderminea (Peck), Harris in Massachns. Agricult. Repos. vol. 7. p. 328. atid tab. annex. 



Habitat : New York, Maryland, Virginia (Drury). 



Male Upper Side. The anteiiiifK and eyes are black ; the thorax and extremity of the body 



eream colour ; the abdomen yellow, spotted on the top and sides with black. The anterior wings are 

 cream coloured, spotted with black. The number of spots very uncertain, except five which are placed on 

 the anterior edge, and six on the external one. Tlie cilia yellow, as are the posterior wings, on each ot 

 which are three black spots, two near the external edge, and one near the middle. 



Under Side. The breast and thighs are yellow ; the abdomen and legs the same, chequered and 

 spotted with black. All the wings are yellow, spotted in the same manner with black, as on the upper 

 side. 



Female. — Upper Side. The head and thorax white. The abdomen yellow, with black spots (rti the 

 sides and top, the extremity being white. All the wings are white, with black spots, whose number is 

 very variable ; but, on the anterior edges of each anterior wing, are placed five, and on the external 

 edges, six. 



Under Side. The legs are black and white, the thighs yellow ; the abdomen white, spotted with 

 black. All the wings are white, with black spots, most of which, observed on the upper side, being seen 

 on this. 



This species is closelv allied to the common British species, Spilosoma lubricepida, 

 and Menthrastri ; but is of larger size, the spots being also larger. The two figures given 

 by Drury, are now ascertained to be the sexes of the same species, as, indeed, our author 

 had surmised might be the case. It appears to be a very common species, and is stated by 

 Drury to breed twice a year, namely, in June and September. The caterpillar is \ ery 

 hairy, and when young is white ; as it advances in age, it acquires a fox coloui", and, in its 

 last skin, becomes ahnost black. Dr. Thaddcus W. Harris, a distinguished American 

 entomologist, to whom I am indebted for many valuable insects of that countrj-, has pub- 

 lished a very interesting notice, in the work above cited, upon this insect, under the title of 

 " The Natural History of the Salt-marsh Caterpillar," under which name the larva of this 

 insect is commonly known, and which is exceedingly destructive to grasses ofvarious kinds. 

 He states, that when nearly full-fed, " they become very voracious, and continue eating 

 all the day and night without intermission. Soon they leave the meadows, aggregated in 

 great numbers, and commence the wandering state, or begin to run, as is the phrase, de- 

 vouring everything in their progress ; corn-fields, gardens, and even the coarse and rank 



