SCIENTIFIC SUMMARY. 
109 
that Audubon, in describing the nest of Vireo solitarius , Vieil., affirms it 
“is prettily constructed and fixed in a partially pensile manner between 
two twigs of a low bush, on a branch running horizontally from the main 
stem, and formed externally of gray lichens, slightly put together, and lined 
with hair, chiefly from the deer and raccoon.” My experience has been quite 
different. Out of the many nests which I have seen and examined, I 
cannot recall a single specimen that will answer to the above description. I 
have five nests of this species, four of which are perfectly similar in struc- 
ture ; the remaining one, formed of the culms of a species of Air a, consti- 
tuting an exceptional case, and the only one that has ever fallen under my 
notice. They are all shallow, loose in texture, scarcely surviving the season 
for which they were designed, and placed between two twigs of a cedar or 
a maple tree, at a considerable elevation from the ground, on a branch 
nearly horizontal to the main axis. They are built entirely of clusters of 
male flowers of Quercus palustris , which, having performed their allotted 
function, don their brownish hue at the very period when they can be 
utilized. Here is evidently a change within a moderately short period, 
rendered necessary by external causes. This necessity may have grown out 
of inability to procure the favourite materials, or a desire for self-preserva- 
tion. In the case of the species under consideration, it cannot be denied 
that the utter inability, without unnecessary physical effort, to procure the 
hair of the afore-mentioned animals, particularly in sections where they 
have been compelled to retreat before the advance of man, may have been 
one of the causes which have induced the change. I am satisfied, however, 
that it has not been the leading one, but that self-preservation has operated 
in this case for individual and family good. The adaptation of the colours 
of the female bird to the tints of surrounding objects, during the trying 
period of incubation, and the establishment of certain resemblances to 
familiar external objects, are two of the ways in which it manifests itself. 
A New Gcinoid-Jish from Turkistan. — The “ Annals of Natural History,” 
vol. xii. p. 269, contains a good translation of a Russian paper, by Professor 
Kessler, on a remarkable fish belonging to the family of the sturgeons, 
discovered by A. P. Fedchenko, in the River Suir-dar, in Turkistan. This 
fish differs greatly from all the known species of the genus Accipenser, in 
which Russia is so rich, and belongs to the genus Scaphirhynchus, esta- 
blished some time ago by Heckel as a North American sturgeon. Professor 
Kessler calls the Turkistan fish S. Fedtschenkoi ; the native fishermen do not 
consider it to be a distinct species, but regard it as only the young of the 
sturgeon of the Aral Sea. They evidently do this in consequence of its nor- 
mally small size, for the largest of twelve specimens examined by Professor 
Kessler was but 8£ inches long, several of them being perfectly mature. 
Dr. Gunther, in a note appended to the translation, remarks that this dis- 
covery is an additional interesting item in the series of instances by which 
the close affinity of the North American, North Asiatic, aud European 
faunas is proved. He quotes as an analogous case the discovery of 
Psephurus gladius in the Yantsekiang, and adds: u After the discovery of 
this species, that of a Scaphirhynchus in Asia might have been foreseen, 
just as I anticipate with confidence the discovery of a Ganoid in Borneo.” 
A New American Pleuronectoid Fish , Glyptocephalus Acadianus, has been 
