214 



Retrospective Criticism, 



existence. I concur in opinion with Dr. Brewster, from having atten- 

 tively examined various mineral substances, but I think a naturalist so emi- 

 nent as Mr. Brown should be answered by facts, and not by conjectures ; 

 and the more so, as Dr. Brewster's opinion, in the same paper, respecting 

 a planetary motion of the molecules, will by many be deemed as impro- 

 bable as Mr. Brown's opinion of their possessing spontaneous motion. 

 Yours, &c. — Robert Bakewell. Hampsteady Apiil 4. 1828. 



Terminology of Birds. — Sir, Your having in your Magazine (Vol. I. 

 p. 121, and p. 276.) furnished us with the technical names of the various 

 parts of birds, shows your anxiety that your readers should be well grounded 

 in the study of ornithology, yet I think your list of names of the various 

 parts of birds are deficient in arrangement, which renders them more diffi- 

 cult to commit to memory than they would otherwise be. I have from 

 these lists arranged one for my own convenience, of which I send you a 

 copy; in it I have omitted the terms " tridactylos," &c., which are not 

 names of a part of the animal, but only descriptive of the formation of the 

 foot. — Thos. Thompson, Hidl^ Sept. 9. 1828. [For more convenient re- 

 ference, two cuts which appeared in Vol. I. are repeated.] 



The principal parts 

 ofbirds are eight, 

 . as follows : — 



l.R6strum, the bill, 

 which is divided 

 '" into 3 parts. 



1. Maxilla the upper part of the 

 bill, which is subdivided into 5< 

 parts {^fig. 51. a) 



'I. Na.res, the nostrils (e) 

 P^rtrum, the hook {d) 



2. Ckput, the head, 

 which is divided 

 into 17 parts. 



3. C61men the ridge (c) 



4. Mesorhinium, the upper rid) 



5. Cfera, wax on the bill {fig. 55 



2. Mandibula, the lower part of the bill {fig. 51. b) 



3. Gbnys, the point of the Mandibula (e) 



1. Lbrum, the naked line at the base of the bill {fig. 51. /, and 5i 



2. Lingua, the tongue. 



3. Fr6ns, the forehead {fig. 51. j) 



4. Capistrum, the face {k) 



5. Sinciput, the hinder part of the head {m) 



6. R^gio opth&lmica, region of the eyes {o) 



7. O'culus, the eye. 



8. O'rbitaB, the orbits or centre of the eyes {fig. 52. o) 



9. Supercilium, the eyebrow (Jig. 51. n) 



10. Tempora, the temples (p) 



11. Gitna, the cheek {q) 



12. Crista, the crest (fig, 52. n) 



13. C(Srnua, the horns. * 



14. Bkrha, tlie beard (rf) 



15. Mentum, the chin (e) 



16. Aures, the ears {fig. 51. p) 



, 17. Rdgio par6tica, protuberance behind the ear (r) 



;e(/) 

 .a) 



lb) 



I 



