308 Dr Prichard on the Varieties 



17-24. Show the principal varieties in the form of the teeth of 



the Rotatoria. 

 17-20. Gymnogomphia. 

 ,.,r 17, 18. Polygomphia ; 17. jaws and teeth separate ; 18. 



i^l pharynx and teeth of Hydatina senta, 



')fU lo aioijii^^' ^^' ^onogomphia ; 19. jaws and teeth ; 20. pharynx, 

 jaws and teeth of Diglenaforcipata, 

 21-24. Desmogomphia. 

 ., . 21, 22, Zygogomphia ; 21. jaws and teeth ; 22. ditto with 

 pharynx ot Rotifer macrurus. 

 23, 24. Logogomphia ; 23. jaws and teeth ; 24. pharynx, 

 ^ ' jaws, and teeth of Megalotrocha atha. 



^STRACT OF A COMPARATIVE REVIEW OF PmLOLOGICAL AND 

 PHYSICAL RESEARCHES, AS APPLIED TO THE HISTORY OF THE 

 HUMAN SPECIES. By J, C. PRICHARDy M. Z)., F, R. S, 



The object of this essay is to furnish a survey of the progress 

 of knowledge in relation to ethnography, with a critical account 

 of the attempts which have been made to distribute the human 

 species into departments constituting what are termed Families 

 of Nations, and especially of that classification of races which 

 has been adopted by Baron Cuvier, and is now very generally 

 received. The author commences with preliminary remarks on 

 the resources of knowledge available in researches of this kind, 

 and states it to be his principal design to consider and estimate 

 the means of information respecting the history of mankind 

 which are furnished by two different methods of inquiry, viz. 

 by philological and physical investigations ; the former including 

 those researches into the structure and affinity of languages 

 which have been undertaken with a view to elucidate the rela- 

 tions of tribes and races to each other ; the latter, the attempts 

 which have been made to classify nations by their mutual re- 

 semblances in figure, complexion, and other physical peculiari- 

 ties* • 'X\M'ilVll:\ U--^-.1^,M-- 



" Philology, 4n ' this point of. view an important study, dates 

 'its origin from an era glorious in the history of modern disco- 

 very and the achievements of science. It begins with the voyage 

 of Malgalhaens, who first led the way in the circumnavigation 



