138 J- DUESBERG 



Salamandra after the period of sexual activity (namely by Meves 

 '91), as once that period over, the testicular conditions are very 

 similar in both the amphibian and the fish. 



The chondriosomes of the primary spermatogonia deserve 

 special mention. In the resting cell they are numerous, coarse 

 and irregular granules or rods. Most of them are located very 

 close to the nucleus and cover its surface. This disposition 

 might be interpreted in favor of Goldschmidt's chromidial theory. 

 Such a claim however would be unfounded: Goldschmidt and 

 his pupils basing themselves upon defective observations, ex- 

 pected to demonstrate that the chondriosomes of the germ-cells 

 were formed during the growth-period and they have failed 

 utterly.^ The continuity of the chondriosomes on the other 

 hand has been demonstrated in a number of animals and is 

 strongly supported for fishes by my observations on the fish- 

 embryo ('17).^ It is however far from my mind to deny the 



^ For a complete historical and critical account of the chromidial theory, see 

 the third chapter of my review ('12). Shaffer, who seems inclined to believe (p. 

 414) in a nuclear origin of the chondriosomes, gives as an argument that "in 

 nearly all the growth-stages of the first spermatocytes, there is present a denser 

 and more deeply staining perinuclear zone," formed by the chondriosomes. I 

 should take exception to this statement, for it is characteristic, even if not quite 

 general, that the male auxocytes have their chondriosomes accumulated at one 

 pole of the nucleus, around the idiozome. 



* In a paper on the testicle of opossum, Jordan ('11) claims that he has demon- 

 strated the discontinuity of the chondriosomes in the seminal cells. I have 

 been investigating lately the same object and my observations are in direct 

 contradiction with Jordan's claim: chondriosomes exist in abundance in all the 

 stages of the evolution of the seminal cells. 



Shaffer ('17) enters against the theory of the continuity of the chondriosomes 

 in the following way; " (p. 423) the progressive increase in the amount of mito- 

 chondria (during the evolution of the seminal cells) seems to indicate that they 

 are differentiation-products. Hence, if there is any genetic continuity between 

 the mitochondria of successive cell-generations, it is only of a limited sort. The 

 conception that the mitochondria present in the somatic cells are the direct 

 descendants of those of the germ-cells, from which thej' have arisen, certainly 

 has very little evidence in its favor." I must state that I entirely fail to see an 

 argument against the continuity of the chondriosomes in the fact that their 

 amount may increase. Concerning the continuity of the chondriosomes in the 

 somatic cells with those of the germ-cells, -Shaffer overlooks apparently the num- 

 erous observations which have shown this continuity, from the egg at least to the 

 embryonic cells. I limit myself to remind of my own observations on the bee, 



