596 A Century's Progress in American Zodlogy. (October, 
tion of his Contributions to the Natural History of the United 
States, mainly devoted to the developmental history of the radi- 
ates and turtles, Agassiz was assisted by H. J. Clark, who, under 
his training, became the best histologist our country has yet pro- 
duced. W. J. Burnett, another histologist, was only inferior to 
Clark. Macrady, another of Agassiz’s students, published some 
papers of importance on the Acalephs and their mode of devel- 
opment. Desor and Girard wrote on the embryology of worms. 
Memoirs of a high order of merit followed, from the pen and pen- 
cil of Mr. Alexander Agassiz. His embryology of the Echino- 
derms appeared between 1864 and 1874 ; the memoir on the Alter- 
nation of Generations of the worm, Autolycus, appeared in 1862; 
his paper on the early stages of Annelids in 1866; his remark- 
able memoir on the transformation of Tornaria into Balanoglossus 
was published in 1873; and his elaborate embryology of the 
Ctenophores in 1874. In 1864, Jeffries Wyman, at the time of 
his death our leading American comparative anatomist and phys- 
iologist, published a memoir on the development of the skate. 
The beautiful memoir of Hyatt on the embryology of Ammon- 
ites was a difficult research, while the brilliant papers of Morse 
on the early stages of the Brachiopod, Terebratulina, published 
in 1869-73, enabled him, by embryological as well as anatomical 
evidence, to transfer the Brachiopods from the Mollusca to the 
vicinity of the Annelidan worms. His studies on the carpus and 
tarsus of embryo birds should also be mentioned. In 1872 Pack- 
ard published a memoir on the development of Limulus, and 
pointed out the affinities of its young to certain young Trilobites ; 
and he also published papers on the embryology of the Thysa- 
nourous, Neuropterous, Coleopterous, and Hymenopterous insects. 
S. I. Smith traced the metamorphoses of certain crabs an 
shrimps. Several entomologists, as Harris, L. Agassiz, Fiteb, 
Riley, Scudder, Packard, LeBaron, Hagen, Cabot, Walsh, Saun- 
ders, Edwards, and others, have studied the metamorphoses : 
insects, while the drawings in illustration of Abbot and Smith’s 
Natural History of the Rarer Insects of Georgia were made by 
Abbot, who lived several years in Georgia. In 18 4 i 
described the embryology of the spider, Pholcus, and durmg t 
present year an important memoir by W. K. Brooks on the anom- 
alous mode of development of Salpa, a Tunicate, has appear is 
We may, then, take an honest pride in the embryological in 
done by American students; for in this department great atl 
ity was shown when scarcely anything was being done in 
