82 Studies on Lije-history of Bonibycine Moths. 



The caterpillar began to pupate between May 9th and 15th, spin- 

 ning' a slight cocoon between the leaves offered the larva (which, 

 however, took no food). The imago appeared about a month later, 

 viz., June 19th. 



Mature larva. — "Length about 30 mm. Head shining black; 

 body purpli.sh-gray ; each segment with dark tubercles (twelve on 

 most of them), each emitting a bunch of shortish spinulated hairs. 

 These hairs are of two colors, the anterior part of the bunch being 

 black, and the posterior pale shining ochreous. Legs reddish-ochre- 

 ous." (Cockerell.) 



The partial life-history of Utetheisa bella (Linn.). 



The eggs and freshly-hatched larvae were kindly sent me by Miss 

 Caroline G. Soiile. The food-plant was Myrica gale. The eggs 

 are laid in confinement, either singly or in patches. The young 

 larva was described August 1st. 



Egg. — About half a millimeter in diameter. When alive it appeared 

 on the leaf to be hemispherical, though rather high, but the alcoholic 

 specimen is certainly spherical. Under a Tolles triplet magnifying 

 10-12 diameters, the living egg is seen to be smooth, shining, with 

 no pits or granulations. The color w^as not noted; but the alcoholic 

 one is yellowish. Under a ^-inch Tolles objective the shell also 

 appears to be smooth, with no granulations visible. 



Larva, stage I. — Length 2 mm. Head large, considerably wider 

 than the body ; dark chestnut-brown, being of the same color as the 

 piliferous tubercles. The body is pale greenish with a yellowish 

 linge. It slightly narrows from behind the head to the end. The 

 prothoracic plate is rather large, bearing four setae on the front edge, 

 and four others on the hind edge. The dorsal tubercles on the 2d 

 and 3d thoracic segments each bear two hairs, the lateral warts 

 each bearing one. The dorsal abdominal tubercles on segments 1 

 to 7 each bear a single hair, though the largest lateral one on the 

 8th segment bears 3 hairs, and the dorsal ones each 2 hairs. The 

 dorsal abdominal tubercles are arranged in a trapezoid, the two in 

 front nearest the median line are larger than tho.se behind, instead 

 of being much smaller, as in typical Arctians, such as Spilosoma, 

 Leucarctia, etc., moreover the trapezoid forms a moderate curve 

 rather than an exact trapezoid. Under a ^-inch Tolles objective 

 the hairs are seen to be very minutely spinulose and tapering; they 



