252 EXTIRPATION OF ORGAN ANLAGEN 



BEFERENCKS : 



Adelmann, H. B., 1937 - "The effect of the partial and complete exclelon of the prechordal 

 substrate on the development of the eyes of Amhlystoma punctatum. " Jour. Exp. Zool. 



75:199. 

 Bodenatein, D., 19'+3 - "An analysis of halancer development in Tri turns torosus." Physiol. 



Zool. I6:l+U. 

 Copenhaver, W. M., 1939 " "Initiation of the beat and intrinsic contraction rates in the 



different paits of the Amhlystoma heart." Jour. Exp. Zool. 80:195' 

 Detwller, S. B., 19^6 - "A quantitative study of locomotion in larval Amblystoma follow- 

 ing either midbrain or forebraln excision." Jour. Exp. Zool. 102:321. 

 Ekman, G. , I929 - "Experimentelle Untersuchungen uber die fruheste. Herzentwicklung bel 



Eana fuaca." Arch. f. Ent. mech. Il6:327. 

 Harrison^ E. G., I92I+ - "The development of the balancer in Amblystoma, studied by the 



method of transplantation and its relation to the connective tissue problem." Jour. 



Exp. Zool. l4-l:3'4-9. 

 Kollros, J. J., I9U0 - "The disappearance of the balancer in Amblystoma larvae." Jour. 



Exp. Zool. 85:33. 

 Petersen, H,, I925 - "Berichte uber Entwicklungsmeckanlk. I." Ergebn. d. Anat. u. 



Entw'gesch. 2it-:327. 

 Eotmann, E. , 1935 - "Der Anteil von Induktor und reagierendem Geweb an der Entwicklung der 



Kiemen und Ihrer Gefasso." Arch. f. Ent. mech. 133:225. 

 Schotte, 0. E., & M. V. Edds, 19'4-0 - "Xenoplastic Induction of Eana pipiena adhesive diaca 



on balancer site of Amblystoma punctatum." Jour. Exp. Zool. 8^:199. 

 Severlnghaus. A. E. , I93O - "Gill development in Amblystoma punctatum." Jour. Exp. Zool. 



56:1. 

 Stohr, P., 1925 - "Entstehung der Herzf orm. " Arch. f. Ent. mech. 106:l4-09. 

 Stohr, P., 1929 - "Zur embryonalen Herztranaplantatlon. " Arch. f. Ent. mech. 109:300. 



'Vitalistic hypotheses assume some sort of intelligence, 

 or will, or psychic principle in organisms themselves that 

 act as guiding or directing causes of adaptation - a sort of 

 deus rn machina. Among these hypothe se s are the ' per fee ting 

 pr inc iple ' of Ar istotle and Nageli, the 'indwelling soul' of 

 Plato and Bruno, the 'active te leological pr inciple ' of Kant, 

 the 'will' of Schopenhaur , the 'desire, need, and appetency' 

 of Erasmus Darwin and Lamarck, the 'unconscious purpose' of 

 Hartmann, the 'vital force' of Bunge, Wolff, and Virchow, the 

 'elan vital' of Bergson, the 'ente lechy' of Driesch, and the 

 'psychism' of Pauly, Boveri, and Spemann. The chief objec- 

 tion to these hypothese s is that they are mere names, ghosts 

 without substance , not open to exper iment or analys is . There- 

 fore they tend to prevent further inquiry and are a hindrance 

 to re sear ch, unless they are recogni zed as s ignpos ts point ing 

 to the unexplored . " 



E. G. Conhlin 19^^ in 



"End as Well as Means in Life and Evolut ion" 



