EUGLYPHA ACANTHOPHORA. 11 



description of the figures) is not distinct from E. 

 alveolata, which is a combination of two species, one of 

 which (fig. 9) he refers to Difflugia acanthophora, and 

 the other (fig. 10) to D. areolata. 



In his determination of the identity of these two 

 species, Ehrenberg, who did not admit Eiigli/pha to be 

 a genus distinct from Difflugia, was right, but not in 

 ignoring both the specific names given to them by 

 Dujardin and adopting his own names for them. 



Perty, in 1849, recognized this distinction, adopt- 

 ing Ehrenberg's name acanthophora for the spined 

 Euglypha, but nearly all subsequent writers have over- 

 looked the determination of Ehrenberg and Perty, 

 using the name alveolata for both the species embraced 

 under it by Dujardin, as well as for his tuberculata 

 which is one of them, so that it is impossible, in the 

 absence of description or figure, or a reference to either, 

 to determine which species is implied. Several authors 

 have, however, used the name tuberculata, and a very 

 few tubercidoxa, the spineless species being implied 

 under either name. 



In 1902 Eugene Penard recognized, as Ehrenberg 

 and Perty had done, that alveolata comprized two 

 species, and he referred the spined form to Euglypha 

 brachiata Leidy, from which it is undoubtedly distinct. 

 This error was pointed out and corrected in 1911,* 

 when a new name, armata, was given to the species, 

 but there was not any necessity for this, the name 

 acanthophora having been given to it by Ehrenberg, as 

 stated above, so long ago as 1841, although it was not 

 published until the following year. His figure clearly 

 shows that the spines are modified scales, and that he 

 only shows four whilst Dujardin shows five is of no 

 moment, the number being variable. 



The question arising is whether acanthophora or 

 alveolata is the name under which the spined species 

 should be known, and in view of the facts that there 

 is no indication as to which of the two forms .would 



* Wailes in ' Proc. R. Irish Acad./ vol. xxxi, pt. LXV, p. 37. 



