294 



MISS EDITH E. BAMFORD ON THE 



II. Variations in Form. — Some radials were broadened distally 

 (text-fig. 56 A), some had two distal epiphyses, others were 

 more or less deeply forked distally (text-fig. 56 B), and some 

 were incomplete (text-fig. 56 0), A perfect gradation was found 

 from the bi-oadened to the deeply forked radial. In 67 fins 

 examined, it was found that 52 per cent, had either forked or 

 incomplete radials or both variations. Of these, 54 per cent, 

 had forked radials only, 23 per cent, had incomplete radials only, 

 and 23 per cent, had both forked and incomplete radials. The 

 incomplete radials were perfect distally, but had no proximal 

 epiphyses and did not reach to the mesopterygium. There seems 



Text-fi^. 56. 



Radials of Folyptertis. 

 A. Broadened Radial, showing indications of forking 

 C. Incomplete Radial. 



B. Forked Radial. 



to have been some difference of opinion concerning the kind of 

 variation that occurred in the radials. Wiedersheim * showed a 

 dividing radial, but Klaatsch found only incomplete radials in 

 two specimens, and he doubted the occurrence of dividing radials ; 

 but that both forms are found (and frequently) is now evident. 

 ISTo forked or incomplete radial is shown in Budgett's larval 

 Polypterus. 



Judging from the position and shape of the proximal end, an 

 incomplete radial in one specimen appeared to be one of the 



* Lehrbucli der vergleichenden Anatomie, Erster Tlieil, 1882, p. 179. 



