coeeesponde:n'ce. 



303 



Tlie column marked " Maccagnone " should have been headed " Mac- 

 cagnone and San Giro," and the species inserted therein are those derived 

 from both localities. 



The Fells, Ursus, Sycpna, Bos. Hipjpofotamus, and Cervus have been 

 hitherto not referred to their species by Dr. Falconer. To obviate further 

 mistake, I append a list of the species derived from both bone-caves, 

 as stated in Dr. Falconer's paper (Quarterly Jom-nal, Geol. Soc. vol. 

 xvi. 1860, p. 99 et seq.) 



San Giro Cave, 

 Two miles from Palermo. 



Felis, a large species. 



Cants. 

 Ursus. 



Cervus. 



Bos. 



Sks. 



Elepha^ antiquus. 



Hippopotamus. \ , • „ 



j^^^ ^ J- two species. 



Maccagnone Cave, 

 A mile west of Cariiii, near Palermo. 



Felis, " as large as F. speltea, but not yet 

 specifically determined."' 



Ursus. 

 Hijcena. 

 Cervus. 

 Do. 



j-two species. 



WepTias antiquus. 

 Hijijiopotarnus. 



Bones of Euminants. 



The liability in a table of this kind to error is obvious, when the 

 exigencies both of space and time are duly considered. 



Before the unenviable employment is commenced by me of "a wholesale 

 manufacture of species," I shall wait the further identification of the 

 specimens from the Sicilian bone-caves by Dr. Falconer. 



Yours truly, 



Chaeles Caeter Blake. 



Origin of Sjoecies. 



SiE, — In the July number of the 'G-eologist'is a letter from Professor 

 King, of Galway, expressing the opinions to which that high authority has 

 arrived, after years of due thought and consideration, on the probable 

 method of operation of continuously-operating secondary laws, which have 

 produced the species of animals successively or progressively throughout 

 geological time. While paying the highest tribute to the candid manner 

 in which this eminent geologist has treated his subject, I am led to suggest 

 that the meaning of one passage in his admirable paper may be liable to 

 misconstruction. 



Professor Xing holds " that an organism, whether it typifies a species, 

 a genus, a family, an order, or a class, is an autotheogen, if it possesses a 

 series of characters which isolate it from other equivalent groups ; " and 

 that inherent and external forces may modify such organism, " thereby 

 resulting in geneotheonomous forms." The limits within which au- 

 totheogeny can be predicted are, however, left unexplained by Professor 

 E^ing. 



A writer in 1830, reasoning from the philosophical standpoint of the 

 state of knowledge in the time of Cuvier, would have confidently pointed 



