CUBAN SEAWEEDS. 207 
wards the zoospores,* are formed. The only species brought by 
Mr. Wright was C. tomentosum (Fig. 55, magnified 200 diameters), 
which is found almost everywhere, in the tropics and temperate 
zones except on our own coast. It is com- 
mon in Europe and California, but, on our 
Atlantic coast, it has not been found north of 
Key West. 
The two orders, Dasycladeæ and Valon- 
iaceæ, are sometimes regarded as forming a 
Fig. 58. 
part of the Siphonacese. Harvey considers 
them independent orders. The Dasycladex 
(Fig. 48, structure of a plant of this group) 
comprise plants of a single axial cell sur- 
rounded at intervals by whorls of branching 
cells. It is a small order, represented in 
the Wright collection by only three species, 
Dasycladus claveeformis, Neomeris dumetosa, 
Acetabularia crenulata. The first named 
looks remarkably like a small sized, dried 
up, birch catkin, devoid of all interest. It 
consists of a large central cell, from the 
sides of which whorls of cells are given off, 
dividing trichotomously and bearing spores 
: . m = Penicillus Phoenix, nat. size. 
in the axils. > The two last species are calca- 
reous. Neomeris dumetosa (Fig. 54, magnified 200 diameters) as 
far as external appearance is concerned, is insignificant enough, 
Fig. 59. color and a granulated surface. 
Viewed with a low power, as half 
an inch objective, it is extremely 
beautiful. The central cell is sur- 
rounded by rings, from which the 
secondary cells are given off with a 
remarkable uniformity. These after 
a while divide, and each division 
bears a large, obovate sporangium 
with a double outline, filled with the 
most beautiful zoéspores. Enveloping the whole is a membrane 
composed of hexagonal cells, on which is the calcareous deposit. 
Anadyomena flabellata, 10 diam. 
* Locomotive spores (or seeds) of the alge. 
