470 Miscellaneous. 



These muscular bundles have a most important part in the re- 

 spiration of these animals. They do not swaUow the air like the 

 Batrachians ; but when they respire, the muscular bundles contract 

 (as the heart itself would do), the air is expelled, and after the con- 

 traction reenters the lungs by virtue of the elasticity of the thorax, 

 aided, no doubt, by the elevator muscles of the ribs. Contractions of 

 the thoracic muscles take no part in the expiration, which is due 

 solely to the muscles of the lungs themselves. It does not seem 

 probable that these pulmonary muscles are subjected to the will of 

 the animal ; it appears to me that they must act like the muscles of 

 the iris, which contract independently according to the intensity of 

 the light. When we observe one of these lizards breathing, the 

 longest respiratory period is that of expiration, followed immediately 

 by a sudden inspiration. When a mammal respires, the contrary is 

 the case ; a long inspiration precedes a shorter expiration. The 

 respiration of the Psammodromi therefore differs profoundly, both 

 from an anatomical and a physiological point of view, from that of 

 Mammalia and Birds. It belongs to an intermediate type, which 

 must take its place below that of the two classes just mentioned and 

 above that of the Batrachia. — Coniptes Bendus, March 3, 1873, tome 

 Ixxvi. p. 585. 



M. Gervais on the Sheleton of the Luth (Sphargis coriacea). 



Two specimens of this Turtle were caught on the coast of France 

 in May 1872. One specimen was sent to Paris ; but it arrived in 

 such a bad state that it could only be made into a skeleton, there 

 being none previously in the Anatomical Museum of Paris. 



M. Gervais has published a paper on this specimen, which, 

 though called adult, is evidently a young one, though the size is not 

 stated ; and he has added some indications of the skeleton of a much 

 younger animal, in the eighth volume of the ' Nouvelles Archives 

 du Museum,' illustrated with five beautiful plates, and describes the 

 skin of a new fossil sijecies as Sphargis psendostracion, found in the 

 blue calcareous strata of Yalergues (Herault). 



This paper confirms the account of the skeleton of this animal 

 given by Dr. Gray in a previous number of the 'Annals.' It would 

 be curious to compare this skeleton with the perfect skeleton from 

 the coast of Demerara in the museum at Stuttgard. 



On an adult Skeleton of Tyrse nilotica in the British Museum. 

 By Dr. J. E. Gray, F.R.S. &c. 



Dr. Baikie sent home a very fine skeleton of an adult Tyrse 

 from West Africa, which has just been mounted ; and it shows 

 peculiarities which have not heretofore been observed in this 

 animal. 



The sternal callosiUes are much broader and more developed. The 



