Mr. J. J. Quelch on Thuiavia zelandica, Gray. 249 



tained by Dr. Jolliffe at Hokianga, Northern Island, New 

 Zealand, in 1851. 



Although there are no gonothecae on any of the type 

 specimens of Th. zelandica, there cannot be any doubt that the 

 description given by Allman applies to this species ; for the 

 other characters on which the identification is based are both 

 numerous and definite. A slight exception may, however, be 

 1 made with reference to the marginal teeth of the hydrothecse 



I an exception also noticed by Mr. Thompson in his specimen. 



These are not uniformly conspicuous. On parts of the pinnse 

 they are as distinct and as regular as those in Allman's figure ; 

 in others they are more or less unequal ; while, again, the 

 margin must often be described as being only irregularly den- 

 tate, irrespective of the number and size of the teeth. The 

 edge of the mesial keel on the sides of the pinnse is not 

 always entire, but in parts becomes slightly and irregularly 

 notched, and often divided into two or more raised lines, which 

 are continued on the basal part of the hydrotheca. This con- 

 | dition is more marked on the distal portion of the main stem, 



\ where the keel is represented by widely notched raised lines. 



b Special mention of these minor points has been made with 



;! reference to another specimen in the collection, which, though 



I I was at first inclined to describe it as a new species, I think 



j must be regarded as a well-marked variety of Th. zelandica. 



i No locality is recorded for the specimen; and gonothecae are 



absent ; so that it is possible that when this additional infor- 

 mation is forthcoming this variety may have to be raised to 

 specific rank. For the present I designate it as Th. zelandica } 



var. valida. 



Thuiaria zelandica, var. valida. 



The specimen of this variety consists of a group of mora 

 than thirty simple stems arising from a mass of closely inter- 

 laced fibres. Its chief difference from the type specimens 

 of the species is its decidedly robust growth. The stems range 

 from 100 to 250 millim. in height; the paired pinnse, from about 

 30 to 60 millim. in length, are placed at intervals of from 4 to 

 5 millim. as compared with pinna3 of about from lOto 20millim. 

 at intervals of from 1| to 3 millim. in the type. Its hydro- 

 theca3 are nearly half as large again as those of the type ; 

 the lateral notches separating them from the hydrocaulus at 

 their upper portion are not so clearly marked ; the marginal 

 teeth are generally wider, more rounded and irregular ; the 

 mesial keel at the sides of the pinnse is less prominent and 

 more frequently represented by the raised notched lines con- 

 tinued to the basal part of the hydrotheca — a condition more 

 niarkedon the distal portion of the main stem than on the 

 pinna of the type of the species. 



