532 FOOT AND STROBELL. [Vol. XVII. 



Meves (20), ('94); Foot (9), ('96), and others. These homolo- 

 gies are emphasized, extended, and most suggestively pre- 

 sented, in Prenant's classic work. Stir le Protoplasma Siipe- 

 rieur (ArcJioplasvie, Kinoplasme, Ergastoplasme) (29), ('98, '99). 

 The homology of the yolk-nucleus in oogenesis to the Neben- 

 kern of spermatogenesis is perhaps the most familiar. As early 

 as 1882 Nussbaum (28) identified the Nebenkern of a variety 

 of gland cells with the Dotterkern of eggs and the Nebenkern 

 of the spermatocytes. On PL XLV we have reproduced (from 

 the works of various authors) figures which appear to show a 

 special cytoplasmic substance that resembles the archoplasm 

 in the Q^g of Allolobophora. We realize the superficial nature 

 of this morphological comparison, and we therefore shall avoid 

 making any assumptions, but hope to aid in the solution of 

 the problem by presenting these likenesses in a convenient 

 form for the cytologist of broader experience to consider. 



Photo ^6, PI. XLV. A reproduction of Auerbach's (i) 

 Fig, 6"^ — Paludina vivipara. " Intermediare Proliferation der 

 primaren Samenzellen. Eine ebensolche ist durch Furchung 

 in vier Tochterzellen geteilt ; in letzteren ist noch wahrend 

 ihres Zusammenhangs die Nebenkernbildung weit vorge- 

 schritten. Vergr. 1000" (cf. Photos 1-6, PI. XLI). Auerbach 

 resrards the Nebenkern as a differentiation and concentration 

 of the general cytoplasm : " Die Zellsubstanz erfahrt eine 

 allmahlich vor sich gehende innere Differenzierung, die zur 

 Bildung eines Nebenkerns ftihrt," p. 443. " Auch hier 

 entsteht ein solcher auf dem friiher geschilderten Wege durch 

 Verdichtung des Cytoplasma," p. 491. The author's Neben- 

 kern contributes to the formation of the spindle, and he regards 

 it as the homologue of Kinoplasm. " Auch in seiner weiteren 

 Funktion erweist sich der Nebenkern als ein Kinoplasma in 

 demselben Sinne wie dasjenige der Pflanzen," p. 445. 



Photos 97, 98, PI. XLV, reproductions of Meves's (20) 

 Figs. 26 and 28 {Salamandm maculosa). " Spermatogonien des 

 erwachsenen Salamanders," Fig. 26 (Photo 97). " Korner- 

 kranz," Fig. 28 (Photo 98), '*Kornermassen zu einem Haufen 



bon fixateur des oeufs d'Ascaris a cette periode, et Dieu salt si nous en avons 

 essayes," p. 79. 



