APPENDIX. 381 
of plasm, quantities of tree-shaped, branching and mobile 
threads (pseudo-feet, or pseudo-podia), which do not become 
retiformly connected. When, however, the Moneron eats 
(Fig. 12), the mucous threads become variously connected, 
form net-works and enclose the extraneous corpuscule which 
serves as food, which the threads afterwards draw into the 
interior of the Protomyxa. Thus in Fig. 12 (above on the 
right), a silicious and ciliated Whip-swimmer (Peridinium, vol. ii. 
pp. ol, 57), has just been caught by the extended mucous 
filaments, and has been drawn into the interior of the mucous 
globule, in which there already are several half digested silicious 
iufusoria (Tintinoida), and Diatomes (Isthmia). Now, when 
the Protomyxa has eaten and grown sufficiently, it draws in all 
its mucous filaments (Fig. 15), and contracts into the form of a 
globule (Fig. 16 and Fig. 1). In thisstate of repose the globule 
secretes a simple gelatinous covering (Fig. 2), and after a 
time subdivides into a large number of small mucous globules 
(Fig. 3). These soon commence to move, become pear-shaped 
(Fig. 4), break through the common covering (Fig. 5), and then 
swim about freely in the ocean by means of a delicate whip- 
shaped process, like the Flagellata (vol. ii. p. 57, Fig. 11). When 
they meet a Spirula shell, or any other suitable object, they 
adhere to it, draw in their whip, and creep slowly about on it by 
means of form-changing processes (Figs. 6, 7, 8), like Protamcebee 
(vol. i. p. 186, vol. u. p. 52). These small mucous corpuscules 
take food (Figs. 9, 10), and attain their full grown form (Figs. 
11, 12), either by simple growth or by several of them fusing to 
form a larger protoplasmic mass (Plasmodium, Figs. 18, 14). 
Puates IT. anp III. (Between pages 294 and 295, Vol. I.) 
Germs or Embryos of four different Vertebrate Animals, namely, 
Tortoise (A and #), Hen (B and F’), Dog (C and G@), and Man 
(D and). Figs. A, D, an early stage of development; Figs. 
EH, H,a later stage. All the eight embryos are represented as 
seen from the right side, the curved back turned to the left. 
