190 Rhodora [NOVEMBER 
seems a safe conclusion to state that this colony is a sterile hybrid of 
members of these two genera. 
The only members of the genera found on the sandy beach of 
Simmons Pond are the common Cyperus dentatus Torr. and Ryncho- 
spora capitellata (Michx.) Vahl.', the plant which has been generally 
known in the northern United States as R. glomerata. The hybrid 
colony has the foliage much firmer and more leathery than in the 
Rynchospora, in this character strongly suggesting Cyperus dentatus. 
The culms are densely cespitose, as in the Rynchospora, and are without 
any suggestion of the elongate stolons of the Cyperus. The cauline 
leaves are rapidly reduced in size, as in the Rynchospora, and the 
axillary and terminal corymbs are strongly castaneous as in that 
plant but with a more pronounced umbelliform aspect, while the 
very slender spikelets have the aspect of those of a Cyperus, being 
linear-cylindric with very numerous (20—40) closely imbricated some- 
what carinate scales. The latter, however, are spirally arranged as 
in Rynchospora but have the characteristic short awn of Cyperus 
dentatus. In the absence of a perianth such flowers as have developed 
show traits of Cyperus but in the large subulate tubercle and the 
secondary spikelets Rynchospora capitellata is suggested. 
It is certainly a very unusual and possibly an unprecedented 
circumstance to find an apparent hybrid between plants of such remote 
affinity as Cyperus and Rynchospora, members of very different tribes 
of the Cyperaceae. The characters, however, are so conclusive a 
blend of those of the two common members of these genera at Simmons 
Pond that it is difficult to avoid the conclusion that this colony has 
thus arisen. Through the kindness of Mrs. Weatherby, who has 
freely given the use of her skill, the habit and essential points of this 
interesting plant are shown in Plate 125. The plant, being of such 
unusual interest, should have a definite name for convenience of refer- 
ence and it is here proposed as 
X Cyperus Weatherbianus, n. hybr.= Cyperus DENTATUS X 
RYNCHOSPORA CAPITELLATA, habitu ut apud Rynchosporam capi- 
tellatam; culmis caespitosis 3-4.8 dm. altis gracilibus laevibus; foliis 
subcoriaceis basilaribus anguste linearibus elongatis, caulinis 5-7 
valde reductis; corymbis subumbelliformibus terminalibus axillari- 
busque, terminalibus 1.3-2 cm. diametro; spiculis confertis valde 
1 See Blake, Ruopora, xx. 27 (1918). 
