33 
[Fewkes. 
manifest protection to the young Crustacean to be sheltered by its 
host appears self-evident and one can on this ground find abundant 
cause for the mode of life which has been mentioned. Moreover, it 
is also a great advantage that the young of the Amphiura be de- 
stroyed. We may then suppose that in the evolution of this man- 
ner of life, after the Crustacean has found a home in the brood-sac 
of the brittle-star, the ovaries of the Amphiura may have been abort- 
ed by the parasite and this habit of destroying the ovary has led 
to a survival of the young Crustacean. That habit becoming he- 
reditary has led to the condition of life as it now exists. Whether 
the ovaries were first used as food, and in that way the habit of 
spaying the Amphiura arose, I cannot say. It is possible that they 
offered a tempting morsel to the Crustacean, and the advantage 
thus gained by the parasite over others has led through heredity 
to the condition which we at present find. 
The following paper was read by title : 
DATE OF THE PUBLICATION OF THE REPORT UPON 
THE GEOLOGY OF VERMONT. 
s 
BY C. H. HITCHCOCK. 
The Boston Society of Natural History has recently published a 
memoir by Jules Marcou upon “The Taconic of Georgia and the 
Report on the Geology of Vermont,” in which an attempt is made to 
state the true date of the publication of this report. As I prepared 
more than half of these volumes for the printer I have thought some 
misconceptions might be corrected by a statement of the facts. 
The printing commenced early in the spring of 1861 under the 
direction of A. D. Hager, one of the authors, who expected to com- 
plete the printing before the year 1862. This would have been ac- 
complished except for his desire to add an appendix, a reprint 
of descriptions of “Lower Silurian fossils” by E. Billings which had 
made its appearance only in November. Even the title pages had 
been printed with the year 1861 upon them before this addition. 
Nevertheless nothing was crowded over into 1862 except the index. 
Everything else was printed in 1861. It took some time to ar- 
range sheets and plates into shape for binding, so that the circular 
announcing that the report “is now ready for distribution” bears 
3 DEC., 1888 
PROCEEDINGS B. S. N. H. 
VOL. XXIV 
