PERFECT INSECTS WITH THE LARVAL HEAD. 11 



chrysalis was developed ; the head of the caterpillar was still present, 

 but its sutures were separated. The dorsal split of the skin reaches the 

 first segment of the abdomen, and the skin of the abdomen is retracted, 

 but still present. 



A similar specimen was observed last fall by Mr. S. H. Scudder. 



Zygaena exulans var. Vanadis. 



Dr. Staudinger, in a paper on the Lepidoptera of Lapland in Stett. 

 Entom. Zeit,, 1861, Vol. XXII, p. 359, records a larval-headed male of 

 this species, found, July 11, near Bossekop. The specimen is fully 

 developed, with the head of the caterpillar. The mouth parts were 

 immovable in the living insect ; the head was fastened to the protho- 

 rax. and moved only by the motion of the prothorax. The latter is 

 fully developed beneath, and with its legs; above there is a horny 

 black vaulted ring, somewhat hairy on the left side. Mr. Staudinger 

 believes it impossible that the head of the imago is enclosed in this 

 larval head. 



Sphinx spec. 



Mr. Trouvelot assured me that he had caught in Cambridge several 

 years ago. a Sphinx with the head of the caterpillar. The specimen is 

 no longer in existence. 



Professor Van der Hoeven, in his quoted paper, p. 274, records that 

 he has seen a caterpillar of Sph. Tilioi which had not been able to cast 

 off in the last moult the skin covering the spine of the tail. The cater- 

 pillar died before the transformation. 



Bombyx Mori. 



Mr. J. J. Bruinsma, in Tijdschrift voor Natuurl. Geschied, 1840, Vol. 

 VII, pp. 257-270, pi. 1, has published detailed observations concerning 

 the same deformity, accompanied by figures. 



Having read Wesmael's paper, Mr. Bruinsma concluded to try his 

 own observations in raising silk-worms. In the course of the summer 

 he found some specimens, which did not agree exactly with Wesmael's 

 butterfly, but seemed interesting for publication. But shortly after 

 Mr. S. Van Leuwen, also interested in the same kind of observations. 

 communicated to him, August 9, a chrysalis with the upper part of the 

 larval head still remaining. The chrysalis was fourteen days old. and 

 had been taken out of a cocoon, in which the skin of the caterpillar 

 was found. The skin showed nothing unusual, except that the head, 

 which commonly remains united with the skin, was broken off. 



