304 THE RECAPITULATION THEORY 



specialised condition characteristic of the horse and 

 its allies, and which may reasonably be regarded 

 as indicating the actual line of descent of the horse. 

 In this particular case, more frequently cited than 

 any other, the evidence is entirely palaeontological. 

 The actual development of the horse has yet to be 

 studied, and it is greatly to be desired that it 

 should be undertaken speedily. Klever's* recent 

 work on the development of the teeth in the horse 

 may be referred to as showing that important and 

 unexpected evidence is to be obtained in this way. 



A brilliant exception to the statement just made 

 as to the want of exact knowledge of the later 

 development of the more highly organised animals 

 is afforded by the splendid labours of Professor 

 W. K. Parker, whose recent death has deprived 

 zoology of one of her most earnest and single-minded 

 students, and zoologists, young and old alike, of a 

 true and sincere friend. Professor Parker's extra- 

 ordinarily minute and painstaking investigations into 

 the development of the vertebrate skull rank among 

 the most remarkable of zootomical achievements 

 and afford a rich mine of carefully recorded facts, the 

 full value and bearing of which we are hardly yet 

 able to appreciate. 



If further evidence as to the value and import- 

 ance of the Recapitulation Theory were needed, it 

 would suffice to refer to the influence which it 

 has had on the classification of the animal king- 

 dom. Ascidians and Cirripedes may be quoted as 



* Klever, " Zur Kenntniss der Morphogenese des Equidenge- 

 bisses," Morphologisches Jahrbuch, xv. 1889, p. 308. 



