250 Transactions. — Botany. 



clature this would be : length 274 fj. ; breadth, 240 p.. All my New Zealand 

 specimens which I can consider as full grown have a length not less than 

 320 ji, and many range as high as 400 fj.. The average difference is shown 

 in the diagram, fig. 16d. 



Secondly, I think the teeth of the lateral lobes are more numerous, and 

 sharper, than those of the European plant, supposing that is that Balfs' 

 figure may be taken as the general form. My figure 16a shows the number 

 and character of the teeth in a full-grown plant. 



Thirdly, and this is probably an important character, the extremity of 

 the end lobe shows divisions which I am not sure that I find in previous 

 descriptions. As shown in fig. 16a, and more highly magnified in 16c, the 

 extremity of the end lobe has the two teeth at the angles, but it is also 

 deeply divided by a median elliptical cleft, and at the opening of this cleft, 

 on each side, are two short spines or teeth, each pair converging so as 

 almost to close the cleft ; and the pairs are not on the same plane, the 

 lower ones appearing as if from a mammillate inflation on the subdivision 

 of the lobe, 



Are these specific distinctions ? I am not prepared to say. With 

 regard to the last, Eabenhorst's phrase is — " lobo polari angusto cuneato 

 prominulo, in apice plus minus profunde sinuato- vel undulato-exciso, 

 angulis oblique truncatis vel bidentafcis." Mr. Archer (in Pritchard, Inf. 

 p. 727,) says, " End lobe very slightly exserted, its angles very slightly 

 produced, bidentate, ends emarginate." Possibly neither phrase can be 

 construed to include such a cleft as that shown in our plant. As for the 

 spines, they might at first sight be taken for those of M.fimbriata, but they 

 are less hairlike than in that plant, and besides there is never any sign 

 whatever here of the spines seen on the teeth of M. jimbriata, in the lateral 

 lobes. 



In my figure 166 I represent a specimen which only once came under 

 my notice, amongst perhaps a dozen of the ordinary form, and which I take 

 to be a young state of the plant. It is smaller in size, but the cleft of the 

 end lobe is there. The angles of that lobe are scarcely bidentate, and the 

 spines at the cleft are inconspicuous. And the teeth of the lateral lobe are 

 of irregular form, some truncate, some sharp. It appeared to me that the 

 specimen was certainly immature. 



On the whole, I hesitate yet as to the identification of this plant, and 

 being unable to make up my mind on the point, leave it as M. rotata. In 

 the character of the endochrome, in the arrangement of the amylaceous 

 vesicles, and in the mode of self-division (as noted in my former paper) it 

 resembles the European species. When a zygospore is found, the doubt 

 may be cleared up, but we may have to wait some time for that. 



