212 



There were neithex' Inter-maxillaries nor lower jaw, though there 

 was a well-formed glenoid fossa for the articulation of the latter with 

 the temporal bone. The two tympanic bones coalesced, but the Eus- 

 tachian tubes opened freely into the cavities of the tympana. 



The cerebral hemispheres, as usual in the Cyclops, were represented 

 by a single and symmetrical cerebral lobe, without a middle division or 

 sulcus. The convolutions were few and symmetrical ; the cerebral walls 

 were very thin in the middle of the upper portion, and the cavity was 

 filled with fluid. 



The olfactory and hypoglossal nerves were deficient, but all the 

 other pairs were traced. 



This specimen belongs to the fourth species of Cyclopism described 

 by Vrolik, with which there coexists deficiency of the lower jaw. The 

 fusion of the tympanic bones with each other shows a tendency in the 

 sides of the base of the head to come together, which may be carried 

 so far, as shown by specimens described by Vrolik, that the alveolar 

 borders of the upper maxillary bones are drawn nearly to the median 

 line, and the eyes, instead of being on the upper lateral region, are actu- 

 ally found on the under surface of the head, and the ears meet in the 

 same region, on the middle line beneath the place of union of the head 

 and neck. In another stage, the maxillary bones, very much reduced, 

 approach each other still nearer ; the malar bones coalesce, as also the 

 palatines and intermaxillaries. 



The last stage of this series of malformations of the head is found in 

 the Perocephalus, in which all the facial and the fi'ontal bones have 

 disappeared, and the other cranial bones are imperfectly developed. 

 The only external parts of the head in this case is a pair of ears. 



Mr. S. H, Soudder exhibited a specimen of Sphinx cine- 

 rea Harris, which had died in confinement while passing 

 from the larval to the pupal state. 



The hinder extremity of the body, from the tliird abdominal segment 

 backward, was entirely like the perfectly formed pupa, except that 

 the swelling at the base of the anal horn in the larva had not entirely 

 subsided, and that the excisions found on the anterior border of the 

 segments at the stigmatal line were not quite fully developed ; but the 

 form, the structure of the anal button and the adjacent parts, with the 

 general sculpture of the integmiaent, were altogether pupal. The ante- 

 rior portion of the body, on the other hand, was almost altogether lar- 

 val ; the head and legs of the caterpillar were there ; the integument 

 seemed to be in a sort of transition state, the dorsum of the thorax 

 showing indistinctly the mapping out of the sutures of the pupal 

 thorax, and even partially the pitting of the surface, while the trans- 



