192 DR. J. E. GRAY ON THE GENUS STERNOTHERUS. [May 26, 



of Matanzas, in the mountains. The birds, though apparently unin- 

 jured, were quite sleepy, not attempting to fly ; the only energy 

 they exhibited was by making their powerful claws meet in my fin- 

 gers when I endeavoured to secure them. I afterwards, on several 

 occasions, observed them flying over the plain with amazing swiftness 

 during dull rainy evenings of July. Later on in the autumn Mr. 

 Hague, of San Gerdnimo, secured for me the nest which I now ex- 

 hibit. He found it, during a visit to some Indian ruins in the 

 neighbourhood, sticking to the under surface of an overhanging rock. 

 The bird was distinctly seen to enter several times ; but Mr. 

 Hague was unable to shoot it, owing to its rapid flight. There were 

 no eggs in the nest. In this nest we see the saliva of the bird used 

 as an adhesive material in nest-building, as in the genus Collocalia 

 of the Old World, but differently applied. At first sight the saliva 

 appears to have been used merely to secure the foundation of the 

 nest (if the term may be applied inversely) to the overhanging pro- 

 jection of rock upon which the rest of the structure is woven, as in 

 the nests of the Icteridse ; but upon closer examination it will be 

 seen that the saliva has been applied to secure every one of the seeds 

 used in the construction of the nest, and in no other way could so 

 firm and durable a structure be attained. Another curious feature 

 will be noticed in this nest, — which is, the false entrance at the side. 

 I remember to have seen a similar tiling in other nests ; I think they 

 were Australian. They appear to be placed there to deceive some 

 enemy, such as a snake or lizard, to the attacks of which the parent 

 bird or its ofi^spring would, during the time of incubation, be more 

 exposed. It would be interesting to know how the materials for 

 this nest were gathered, whether from the plant itself, or caught in 

 the air by the bird as the seeds were carried by the wind. /^ 



3. On THE Species of the Genus Sternoth^rus, with some 

 Observations on Kinixys. By Dr. J. E. Gray, F.R.S., etc. 



The shell or thorax of the Sternothceri off'er such diff'erent appear- 

 ances, according to the age or other special conditions under which 

 they have lived, that it is almost impossible to distinguish them ; 

 and the more specimens are received, the greater becomes the diffi- 

 culty. Under these circumstances, as the heads seem to present 

 some characters which, as far as I have been able to observe them 

 in the limited number of specimens which come under my exami- 

 nation, seem permanent, I have attempted to define the peculiari- 

 ties presented by the heads of the specimens in the Museum Col- 

 lection from different localities. The species were so diflScult to 

 distinguish by means of the shell only, that, in my ' Catalogue of 

 Shield Reptiles in the British Museum,' I stated that all the spe- 

 cies there noticed "perhaps may prove only to be varieties of the 

 same species, or dependent on age" (p. 52). 



A larger series of specimens from the same locality has shown 

 that such characters as the shape and thickness of the shields, and 



I 



