THE BRAGHI0P0D8. 
55 
, growing m cominuni- 
the commonest objects of the sea-shore. They are minute, 
almost microscopic creatures, 
ties of cells, forming patches 
on sea-weeds and stones (Fig. 
58, Memiranipora solida). Cer- 
tain deep-water species grow in 
coral-like forms (Fig. 59, Myrio- 
zoum subgracile), while the chit- 
inous or horny Polyzoa are often 
mistaken for sea-weeds on the 
one hand, and Sertularian Hy- 
droids on the other. 
The animals inhabiting the 
microscopic cells are worm-like 
creatures (Fig. 60), with the di- 
gestive canal bent on itself and 
ending near the mouth, the lat- 
ter surrounded, as in the larger 
fresh-water species (Fig. 60, br), 
with a horseshoe-shaped crown, 
or in the smaller marine forms fig. go.- orgamzation of a Poiy- 
zoon. A, Paludicella Ehrenbergit. 
a Circle of slender ciliated ten- B, Plumatella fruUcosa. br, ten- 
, rm <» 1 J P tacular branchiae of lophophore; 
tacleS. The iresh- water forms ce, oesophagus; stomach; r,m- 
(T-»7 .77 ,\ , testine; a, anus; i, cell; x, poste- 
rlumateila, etc.) secrete no nor, anterior cord, at the in- 
r^^i:^ «l>^ii ..^^ ^^r. sertionof which into the body the 
solid shell, and are either moss- generative products are devel- 
liVp nr form loro-P rnnnrlprl oped; ^, testes; o, ovary; m, re- 
llKe, 01 lOrm laige rounaea tractor muscles of the anterior 
masses of a jelly-like substance.* ?eTra2?o?^muscT^^^^ '''''' p^'^'^'^'p^^ 
Class V. — Brachiopoda {Lamp Shells). 
General Characters of Brachiopods. — This group is named 
Brachiopoda, from the feet-like arms, fringed with tenta- 
cles, coiled up within the shell, and which correspond to 
the horseshoe-shaped crown of the Polyzoa and the crown 
of tentacles of the Sabella-like worms. From the fact that 
the animal secretes a true bivalved, solid shell, though it 
is usually inequi valve, i,e,, the valves of different sizes, the 
See the works of Allman, Hinks, Smitt, Saleusky, Sais, etc. 
