WENRICH: spermatogenesis of PHRYNOTETTIX MAGNUS. 97 



and these conjugant-halves become separated in the second matura- 

 tion mitosis, the result being, therefore, a reductional division. I am 

 thus able to support the careful studies of McClung and his students 

 as to the orientation of the tetrads in the first maturation spindle, 

 where the spindle-fibers become attached at the so-called 'synaptic' 

 or proximal ends, and therefore bring about an equational division. 

 I can likewise support the findings of those investigators who describe 

 parasynapsis. If we accept the view that one of the longitudinal splits 

 is in reality the line of separation between parallel conjugants, we can 

 also accept the observations of De Sinety ('01) as to the existence of 

 two longitudinal divisions. 



McClung and those of his students who have worked on orthopteran 

 material have derived their results from studies confined largely to 

 spermatogonia and the postspireme stages. There is nothing in any 

 of their figures, however, which would be incompatible with parasynap- 

 sis. And the figures by Sutton ('02, fig. 5a, 5b, 6 and 7) of early 

 postspireme stages in Brachystola are much more satisfactorily inter- 

 preted from the standpoint of a preexisting parasynapsis than from 

 the standpoint of telosynapsis. I may also state that I have recently 

 examined some Brachystola material and am well satisfied that the 

 conditions there are quite comparable to those prevailing in Phry- 

 notettix. McClung in his latest paper ('14) accepts the possibility 

 of parasynapsis, and Robertson, who in 1908 argued foi- telosynapsis 

 in Syrbula in no uncertain terms, has recently found parasynapsis in 

 the Tettigidae (Robertson, '15). 



A glance at the outline of the results of orthopteran studies given 

 above reveals the fact that parasynapsis has relatively few adherents. 

 I believe the failure to recognize this important stage has been due (1) 

 to the general unfavorableness of these synapsis, or lepto-zygotene, 

 stages foi" the elucidation of the conditions and a consequent failure 

 properly to interpret them, or (2) to attention having been largely 

 confined to the postspireme stages. That a study of the latter stages 

 could allow of quite diverse interpretations, I am keenly aware, for it 

 was not till I undertook to follow the history of individual chromo- 

 somes that I was able to arrive at any satisfactory conclusion as to the 

 sequence of events. I am confident that the use of the same method 

 on other material will reveal conditions similar to those that I have 

 described for Phrynotettix. 



Where the chromosomes differ among themselves as to shape, as 

 they do in Stenobothrus, another source of confusion is encountered, 

 for very few authors have recognized the fact that cliromosomes of 



