Mr. J. S. Gaskoin on a peculiar variety of Mus Musculus. 93 



Mr. Cassin, in a very useful Synopsis of the North-American 

 Parince, given in his excellent volume on the Birds of California, 

 Oregon, &c., p. 20, mentions two North-American species of this 

 genus, Psahria minima and P. melanotis, but says nothing of the 

 present bird, with wbich he seems to have been unacquainted. Ex- 

 amples of both the former species are contained in the British Museum, 

 and upon comparison agree in every essential character with this bird. 

 It is true that its yellow face and chestnut bend of the wing are quite 

 different in cast of colouring from what we meet with in the other 

 species of this group, and I have little doubt that some naturalists 

 who are fond of coining new names would consider this fact a suffi- 

 cient excuse for making it the type of a new division. But I do 

 myself think that generic characters ought only to be founded upon 

 differences in structure ; and as in the present instance there appears 

 to be none such, I think we shall be quite accurate in registering the 

 present bird as a third American species of the Asiatico-American 

 genus Psalti'ia under the title of 



PSALTRIA FLAVICEPS. 



^ffithalus flaviceps, Sund. Ofvers. af Yet. Ac. Forhand. vii. 

 p. 129 note (1850). 



Conirostrum ornatum, Lawrence, Ann. Lye. New York, 1851, 

 p. 113, pi. 5. fig. 1. 



P . fuscescenti-cinereus, suhtus dihitior : pileo et gutUire flaves- 

 centibus : campteriis dare castaneis : alis caudaque intus nigri- 

 canti-hriinneis : rostra et pedibus 7iigi'is : tectricibus subalaribus 

 albis. 

 Long, tota 4 "2, alse 2'1, caudee 1'9. 

 Hab. Texas (Lawrence^. 



Note. — Since writing the above, I have been enabled through Mr. 

 Gould's kindness to compare Psaltria fiaviceps vnth the type of the 

 genus, Psaltria exilis, from Java. It certainly offers a more pointed 

 beak and wing not so rounded as the latter bird, and may be con- 

 sidered as rather aberrant in form. Any naturalist, therefore, who 

 is unwilling to class it with true Psaltria may use for it the generic 

 term Psaltriparus, that name having been bestowed by Prince Bona- 

 parte (Compt. Rend. Ac. Sc. Par. xxxi. p. 4/8) on Psaltria mela- 

 notis (Sandbach), with which species this bird agrees in every 

 respect. 



On a peculiar Yariety of Mus Musculus. 

 By John S. Gaskoin, F.L.S. 



Mus Musculus. Y'ar. Mus nudo-plicatus. 



I have thus designated this strange and novel form of the genus 

 Mus, to give the more importance to the singularity. 



In the spring of 1854 a labourer in the employ of Mr. Webster, a 

 tenant on the Taplow-court estate, observed several little white crea- 

 tures running about a straw-rick in the wood at the back of the lodge 

 near Taplow paper-mills. Maidenhead Bridge, and succeeded in 



