104 University of California Puhlications in Botany [Vol. 6 



Scinaia Cottonii is represented by two specimens in Herb. E. M. 

 Holmes (No. 9) in the University of Birmingham, collected at Enoiira, 

 Japan, by Saido. Through the kindness of Mr. A. D. Cotton of the 

 Royal Botanical Gardens at Kew I have been able to examine a tracing 

 of one plant and through the kindness of Professor G. S. West, of 

 the University of Birmingham, I have been able to examine a photo- 

 graph of, and a bit of the other. From these the description has been 

 drawn up and a name given to this species. Unfortunately I have 

 been unable to study the structure of the cystocarp. 



Scinaia Cottonii is very close to Scinaia latifrons. from which it 

 differs in smaller size, slightly different dimensions of the utricles, and 

 less marked intramarginal aggregation of the cystocarps. It differs 

 from Scinaia complanata in much greater breadth, shape and dimen- 

 sions of the utricles, and the tendency towards intramarginal aggrega- 

 tion of the cystocarps. 



III. Cylindrical, Normally and Fairly Regularly Constricted 



Species 



J. G. Agardh (1876, p. 513) has referred a constricted form under 

 Scinaia furceUata as var. suhcostata, but the regularity and frequency 

 of the constrictions are not definitely described. There are. however, 

 five species which seem to be cylindrical and normally more or less 

 regularly constricted. Two of these are inhabitants of the southern 

 and central Pacific Ocean, one inhabits the northern Pacific Ocean, 

 while the other two are found within the proper confines of the Indian 

 Ocean. The two former have the utricles broad and only slightly 

 elongated with a scanty development of the corticating layer, while 

 the two latter species have more or less narrow, palisade-like utricles 

 and a broad, dense corticating layer. The fifth species, in the North 

 Pacific Ocean, is temporarily to be referred here. The joints of the 

 first two species are short (or at least shorter) proportional to the 

 diameter, while the points of the other three are long (or at least 

 longer) proportional to their diameter. The jointed species may, so 

 far as present knowledge is concerned, be looked upon as austral 

 rather than boreal in distribution and possible origin, especially since 

 no cylindrical and continuous (i.e., unconstricted) species of Scinaia 

 (as here limited) occurs with certainty in the Southern hemisphere. 

 It is possible that farther search may, however, invalidate this 

 statement. 



