296 Transactions.— Botany. 
9. Scenedesmus quadricauda, R., xxxi. 
= obliquus, R., xxxi. 
- obtusus, R., xxxi. 
I have included the Pediastree in this family for the sake of convenience, 
although the definition of the Desmids as given by both Hassall and Ralfs 
would exclude them, and Carpenter arranges them as a separate family. 
(When this paper was read I had not seen Mr. Maskell’s article on the 
Desmidi of Canterbury.* Since then I have considerably modified my 
remarks on this family, in order to avoid useless repetition and to bring 
it as far as possible into accordance with Mr. Maskell’s paper). 
Micrasterias ampullacea, var. (a) from Ruataniwha. 
” var. (3) Ruataniwha. This plant resembles var. 
B, in ‘sactial outline, but differs in the smoothness of the edges of the fronds, 
in the flatness of the tips of the segments of the lobes, and in the absence 
of puncte inside the margins of the frond. The flask-like shape of the 
segments is very marked. I have placed it under the head of M. ampullacea, 
var. 8, for the present, but I am not sure that it will remain there per- 
manently. Fig. 6. 
Cosmarium cucumis? I have marked this with a note of interrogation, 
because I have seen only one specimen. It corresponds, however, so entirely 
with Ralfs’ description in the smoothness of the frond, the deep constriction, 
and the equality of length and breadth, and the rotundity of the ends of 
the segments, that I have little doubt as to its identity. 
Cosmarium tetraophthalmium is common. 
e margaritiferum abundant. 
»  8p.n. Frond quadrate, slightly longer than broad, not 
deeply constricted. Segments conical truncated, united at the truncations, 
edges smooth. End view circular. This plant is remarkable for its peculiar 
hour-glass shape. I have found no deseription of anything like it in such 
books as have been accessible to me. If it prove a new species I should pro- 
pose the name of C. clepshydra. Fig 7. 
Staurastrum, sp.? Edges of frond smooth, segments united below. 
divaricating. Upper and outer borders concave, uniting at an acute angle, 
inner slightly convex, lower rounded. On the upper concave border x 
three hyaline processes with smooth sides and flattened ends. At junction 
of outer and lower borders is one process similar to the upper ones ie 
eurved slightly outwards. This little plant is unlike anything in Ralfs— 
it might be an unusual form of S. leve, but in the latter the processes are 
forked, in the former not. ~ & 
Closterium. tn thin ees bs sec hee vag eerie et : 
be be referred to Ralfs. oo : 
2 TEE i a a a eT . 
