a 
Botany and Looloyy. 157 
himself, who appears not to have set great store by his own con- 
ception, would have hailed Mr. Brooks’s version of it as an improve- 
me would have pounced at once upon the fact (which the 
n 
Something tangible for the hypothesis to rest upon. But it will 
not be easy to prove that variation, commonly originating in 
reproduction, but sometimes without it, is due to the male 
element. 
The proof-reading of this volume has been negligent, names of 
persons are sometimes wrongly written (Vilmorin is hardly recog- 
nizable as Vilmore); in a great gathering of facts some question- 
able ones find a place; and now and then there is an opinion or a 
bit of reasoning that may be assailed. A: @. 
- fieports on the Results of Dredging under the Supervision 
of A. Agassiz in the Gulf of Mexico (1877-8), in the Caribbean 
Sea (1878-9), and along the U. S. Atlantic Coast (1880), by the 
Coast Survey Steamer Blake.—Report on the hint by A. 
AGassiz. 94 pp. 4to, with 82 plates. Memoirs of the Mus. 
Compar. Zool. at Harvard College, vol. x, No. 1.—Besides the 
of the Pacific genera remain until now unchanged; while Atlantic 
types have been added that previously found less favorable condi- 
tions for their development than those which now exist. e view, 
g 
hg, has not been sufficient to effect any very radical e in 
the Echinid fauna of the two sides.of the Isthmus. Phy 
Conditions, the a r observes, are so nearly alike on the two 
the Jurassic; 10 to the Cretaceous; 24 to the early Tertiary; 
and only 4 to the later Tertiary. Seven of the genera are repre- 
