DIOONTTES. 49 



latter form as having 5-6 veins in each leaf segment, whereas in 

 D. Kotoei there are 7-14. In Schenk's figure of Mantell's species 

 there are eight or nine veins shown, and in the solitary specimen 

 in the Rufford Collection there appear to be at least eight veins. 

 The greater length of the segments is another point referred to by 

 Yokoyama as a specific character of his plant ; but it is difficult 

 on comparing the published figures of the two species to detect any 

 distinct difference in this respect. On the whole, I am unable to 

 discover any sufficient difference between the two plants to warrant 

 the retention of Yokoyama's specific name. Ptilophyllum oligo- 

 neurum, Ten. -Woods, 1 also agrees closely with the English species. 

 In speaking of Pteropliyllum Itichtkofeni, Schenk, from China, 

 Schenk 2 suggests that probably some of the fragments so named 

 may be identical with Dioonites Brongniarti; there is certainly 

 a close correspondence between the two forms, but perhaps 

 hardly a sufficiently strong resemblance to justify the inclusion 

 of the Chinese specimens in the synonomy of Mantell's species. 

 The plant figured by Schenk 3 as Pterophyllum cequale, Brong., from 

 Persia, resembles Dioonites Brongniarti. In Schenk's specimen 

 the pinna? appear to be inserted on the upper surface of the 

 rachis, and not laterally as the generic term Pterophyllum implies. 



V. 2748. 26 cm. long. The alternately disposed pinnae are 

 attached to the middle of the upper face of the frond axis. 

 Venation clearly marked. The lower margin of the pinnae is 

 curved gradually upwards, cutting off the veins obliquely, and 

 the upper margin is practically horizontal. The segments are 

 somewhat less than those in Mantell's figure, but there can be 

 little doubt as to the specific identity of the specimens. Eccles- 

 bourne. JRuford Coll. 



1 Jack and Etheridge (A.), pi. xviii. fig. 11. 



2 Richthofen (A.), China, vol. iv. p. 247, pi. xlvii. fig. 7, and pi. xlviii. 

 figs. 5, 6, and 8. 



3 Schenk (A. 7), Bibl. hot. vi. pi. v. fig. 23. 



