Hyatt.] 
90 
[November 3, 
My conclusions are, therefore, that under different circum- 
stances and perhaps with different conditions as to food, etc., the 
lobster varies the mode of moulting, either crawling out of his 
shell as the Cray-fish does between the carapax and first abdom- 
inal ring, or by splitting open the carapax also, as in the cases 
recorded, and that the latter of these ways may be varied accord- 
ing to which ever end he may select to draw out first. It would 
probably be impossible for the lobster to draw the tail out first, 
if the carapax did not split so as to let the body arch outwards. 
The phenomena of absolution as described by Mr. Wheildon were 
observed upon the inner sides of the first joints of the great claws 
and Mr. Johnson’s discovery fully confirmed. The shell was also 
very much affected by absorption in other parts, especially along 
the sutures of the carapax, and the sutures of the thoracic rings 
had largely disappeared from above. 
Mr. B. H. V an Vleck, Assistant in the Museum, and Laboratory 
of the Society, has, however, made special studies in this connec- 
tion and will communicate his results. 
Mr. B. H. Van Vleck supplemented Professor Hyatt’s account 
with some observations on the extrication of the lobster’s endo- 
skeleton during moulting. He also showed some of the strangely 
malformed claws with false pincers, the explanation of whose 
growth is very difficult. 
Mr. Putnam exhibited a very fine and interesting piece of 
pottery, recently received at the Anthropological Museum in 
Cambridge, from a burial mound on the St. Francis River in 
Arkansas. 
The vessel was in shape like a human head. The features were 
remarkably well made, and Mr. Putnam believed, from the 
peculiar character of the work, that it was very likely a good 
representation of the features of the people among whose bones 
it was found. He then compared the jar with other work of a 
similar character from Central America and Peru, and showed 
that, notwithstanding there was such a general resemblance 
among these vessels of human shape, from various places, as to 
lead people to say they were all of the same character and stage 
of art, they were, after all, very different, and expressed several 
