Botany and Zoology. 133 
printed, and although most of them are in outline they serve admirably 
for this class of subjects. While many of the figures have appeared 
before in Agassiz’s Contributions, vol. iii and iv, Sea-side-Studies i in Nat- 
History, vol. ix, very many new ones appear in this work for the first 
time, and illustrate many species either ose} new or exigency de- 
scribed or figured before. 
Tn_addition to the descriptions of the species there is also given a great 
amount of information concerning their embryological development and 
growth and anatomical characters, which renders the work far more val- 
uable than a mere descriptive catalogue. The synonymy is also much 
more complete than usual in similar works. The author has, in fact, 
brought euibines in a condensed form nearly all the information hitherto 
peri concerning the = of North America, and has added very 
much that is new and ori 
To 1h general remarks ioesiiaais hae age the various conflicting 
Views of authors are discussed and new facts in their embryology are 
brought forward to prove them to piles actually the highest order 
of Acalephs, and especially to show that their bilaterality is more appa- 
rent than real. The evidence adduced seems fully sufficient to establish 
their true position, but we cannot see that their bilaterality is destroyed 
thereby, or that this conflicts with their Acalephian character, since bi- 
sa is also a fundamental feature of both Polyps and Echinoderms, 
r. Ag shows that the ae a is no more bilateral than 
any anesetad gs jelly-fish, but becomes more so by its changes during de- 
velopment. The author, i in fact, anita their bilateral structure when he 
fays: “ Examines in the light of prophetic beings, the bilaterality of the 
Acalephs is but another of those wonderful links which unite in one great 
whole the different members of the animal kingdom” (p. 11). But on 
a previous page he says: “ Bilaterality seems at first sight to be the plan 
upon which these animals are built; but an elimination of the deceptive 
co-efficients will show the plan of radiation —- this apparent - 
It 
has hitherto appeared in this country relating to Acalephs. We regret 
only that the genera already known, but often imperfectly characterized 
in previous works, have not been described in this. The reason for the 
omission is not apparent, since in the preceding rege on Ophiurians 
by Mr. Lyman, the genera, both old and new, are well agree 
8. Fossil Meduse.—Professor Hacxen of Jena, who in 1865 maalked 
attention to the existence of well preserved Meduse in the pi Ras 
slates of Eichstadt, belonging probably to the families of Alquoride 
