120 bulletin: mfseum of comparative zoology. 



names ^ are thus definitely associated with specimens in the Peale 

 Museum. That the specimens thus referred to by number were in 

 all cases the subjects that he drew and described cannot be affirmed, 

 but is highly probable because even in the case of an extremely abun- 

 dant bird, like the Robin, of which there must have been several speci- 

 mens in the Peale Museum, he cites but one specimen or rarely two. 



Wilson's custom of drawing from a mounted" specimen affords a 

 clew in some instances for tracing the subject of his pencil. In the 

 absence of original data, we are forced, like Polonius, to find directions 

 out by indirections. When Wilson drew his bird in a simple, conven- 

 tional attitude, agreement between his drawing and a mounted 

 specimen in the old collection will obviously be of slight significance, — 

 an accidental co-incidence, perhaps, since the same correspondence 

 will in all likelihood hold true of birds in divers museums, the work 

 of divers taxidermists. When, on the other hand, he depicts a bird 

 in an unusual or singular posture, conformity of specimen and figure 

 may fairly be taken as evidence that they bear to each other the 

 relation of subject and copy; the weight of the evidence being in 

 strict proportion to the preciseness of the similitude. In a few cases, 

 individual peculiarities of plumage may assist in identifying the origi- 

 nals of Wilson's figures. 



It does not follow conversely that specimens which do not conform 

 to Wilson's figures are not the subjects that he drew: the exigencies 

 arising from the arrangement of the figures might often compel him to 

 adapt the posture of the bird to the requirements of the plate. With 

 the disappearance of the original Peale labels the chance of recovering 

 most of Wilson's types vanished for ever. 



Can types ascertained by intrinsic evidence, in the absence of lawful 

 credentials in the form of original labels, be of any practical use? I 

 think they can. Let us suppose, in the way of argument, that it is 

 found convenient to separate a species, Mniotilta varia for example, 

 into two races or subspecies, differing from each other in size or plum- 

 age. In the synonymy of this species stands Certhia maculata Wilson. 

 Will the name maculata be usable for the supposed new subspecies? 

 In order to decide this, it seems to me that it would be incumbent 

 upon the reviser of the species to examine, in the absence of a more 

 authentic type, a specimen in the Boston Museum collection which 

 exactly agrees with Wilson's drawing of Certhia maculata; for we know 

 it was a habit of Wilson's to draw from a mounted specimen; that his 



1 Names borrowed by Wilson from William Bartram (Travels through North and 

 South Carolina, etc., 1791) are allotted to Wilson, since their validity depends on his 

 adoption of them. 



