REVIEWS AND BOOK NOTICES. 47 
To this deficiency in the definitions, otherwise so full, we shall re- 
cur in noticing the author’s conclusions as to the more immediate 
relationship of the Brachiopoda. It may 
also be noticed that in none of the dia- 
grams of the transverse sections of the 
worms are the positions of the dorsal ves- 
sel or nervous cord in relation to the body 
walls indicated; and in this respect the 
same view of the mollusk is unsatisfac- | 
tory. This is said not so much by way of 
criticism, as to call attention to important Portion of Peduncle of Lin- 
i gula pyramidata, showing an- 
differences between the Brachiopods and nulations, and circulation of 
Cheetopodous worms, which demand seri- 
ous consideration in accepting the conclusions as to the precise 
systematic position of the Brachiopods claimed by the author. 
Farther on, in speaking of the general proportions of the body, 
it seems that the author does not lay much stress on the ringed 
Fig. 19, structure of the higher worms, of which it 
NEL should be borne in mind he considers the Brach- 
iopods to form a division. Thus it is stated, 
almost casually, that ‘‘a prominent character of 
the higher worms is the annulations or rings 
marking the body.” As, however, the annula- 
tions are wanting in certain low worms (i.e. the 
Notre bel co- Gephyrea or Sipunculoid worms, Sagitta, Nema- - 
median dorsa] t0idea, Acanthocephala*) the absence of this 
notch; 1, lateral noteh. character in the Brachiopods is unimportant; 
still, however, the peduncle 
Ree is “partially annulated” 
(Fig. 18). 
The comparison between the 
mollusks and worms is then ex- 
Fig. 18. 
Fig. 20. 
suggestive way, the author a Head of Discina. Head of Sabella. 
that in the worms the integum 
is rarely ever extended bond x limits of the body ; but when 
*It shonld be borne in mind that these worms are mostly parasitic, or, as in Sagitta 
ee very aberrant forms, and the absence of rings is probably a secondary 
or se alapin ive character. 
