er, 1887. Vol. XXI., No. u 
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T= RUMINANTS (continued). [Illustrated.] Tree in the Black Hills.—Still another Tumble- Weed. 
; 88 
Bee ey eee ee 5 —Botany in the A. A. A. 5. —Botanical News. . 
> na T n smg VEGETABLES (continued). Æ. D On the Homologies of the baie T ; 
se ee ce 903 Veins of Insects.—The Genera o of North Am Mi 
ac. = o OF VERTEBRATA. Phala o o nr 
a r a e ee ee gg 913 | Zoology.—Key to the Recent Families of Sponges. | ! 
—Oceurrence of Stisostediu: veum in the Basin © © 
e IN THE DRIFT, OR SUBAQUEOUS 
OF THE DRIFT, IN CENTRAL MISSOURI. 
strated.) P E Ger o a 917 
teatated 
the Morphology of Ribs. — Zoological News. 
se Fe ere ee 922 
LITERATURE. Embryology: —Spermatogenesis in ien re 
C K 
Fresh-Water Algæ of the United States . . 923 Psychology. Scientific Thesm <- rr 
-a ei The Naples Water-Bath. . F a 
White agh L ney —Scott and Osborn on reti o 
W malia.—Marsh on New Fossil 
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