462 APPENDIX. 



have come under my notice of late years, are by Mr. Blyth,. in Charles- 

 worth's Mag. Nat. Hist, for 1837, p. 81, and Mr. Eyton, in the same 

 volume, p. 358 ; the former introduces the subject in a paper on 

 " Psychological Distinctions between Man and other Animals," and 

 the latter in one bearing the title of " Remarks on the Theory of 

 Hybridity." Mr. Westwood, in 'Trans. Entom. Soc' vol. iii. p. 196, 

 has a paper entitled " Description of a Hybrid Smeriuthus, with re- 

 marks on Hybridism in general." Dr. S. Moreton, in the American 

 Journal of Science for 1847, published a memoir on the general sub- 

 ject, entitled " Hybridity of Animals considered in reference to the 

 question of the Unity of the Human Species." 



A FEW NOTES ON THE MOULTING OF FEATHEKS IN SPRING. 



So little attention has been bestowed on this subject, that I copy a 

 few casual notes. Adult birds of the Lams mariims, L. argentatus, and 

 L. canus, having the head and neck speckled all over with blackish 

 feathers in winter, though of the purest white in summer, suggested 

 the question how this change was effected, and on examination of those 

 parts of the bird, at the vernal season in various years, new, or pen-feathers 

 were found springing, as in autumn, preparatory to the general moult. 

 There was, however, a general thinness or deficiency of j)lumage on the 

 heads and necks of these species, until the pen-feathers were matured, 

 so much so, that the chief taxidermist in Belfast considered birds killed 

 from the end of Etbruary until the full summer plumage was attained, 

 unfit to be set up. In like manner, these pen-feathers were found in 

 that portion of the head of the Larus ridibimdus which is white in 

 winter and black in summer. 



La?'us argentatus. March 14, 1848. — Of two adult birds shot to- 

 day in company, and which probably had paired, the smaller one 

 (proved by dissection a male) has the head and neck wholly white ; — 

 on examination, a great many white feathers, in a young state, appear. 

 The larger bird {female) exhibits more than one-third of the brownish- 

 grey winter feathers on the head and neck. New white feathers appear 

 plentifully in pens on those parts, and a very few are apparent at the 

 anterior part of the back and belly. The ova, in this individual, did 

 not exceed one-third the size of an ordinary pea. 



February, 1849. Adult bird examined early in the month, had the 



