438 Deep-sea Trawling off the S.W. Coast of Ireland: 
One of the most interesting discoveries of the Drs. Sarasin 
was that of the muscles which divide the test into a series ot 
compartments and appear to be the agents in the vermicular 
contractions of the living test; this again they have made one 
of the characteristics of the Echinothuriide, and here, again, 
they have unfortunately argued from the particular to the 
general. These “ Liingsmuskeln ” are altogether absent from 
Phormosoma. An interesting proof of this may be easily 
afforded : if a Phormosoma be opened and water poured into 
the test the whole test swells up; if a quadrant of an Astheno- 
soma be laid open and water poured in the whole test does not 
swell up, and such a specimen if returned to spirit will be 
found to float with one quadrant upwards, just as though 
it were provided with air-tight compartments; these, of 
course, are the “ Kistchen”’ of the Sarasins. Iam not, how- 
ever, sure that, even confining ourselves to the genus Astheno- 
soma, as at present defined, we can always speak of the 
longitudinal muscles as being well developed; they certainly 
are remarkably well developed in Asthenosoma Grrubit, but 
they are very poorly so in the smaller A. pellucidum. With 
the absence of the muscle is correlated that of the Kistchen, 
and with that of the Kiistchen the peculiar loop of intestine 
in each alternate compartment. I do not like to lay too much 
stress on the apparent absence of the organs of Stewart from 
Asthenosoma Grubii and A. pellucidum ; delicate membranes 
might well be injured or collapsed in specimens all of which 
were collected before 1876 (that is, of course, during the 
cruise of H.M.S. ‘ Challenger’), and I am not saying they 
are not to be found in all species of Asthenosoma; I have, 
however, some doubt as to whether or no they are so large or 
so constant as they seem to be in A. urens. 
However that may be, the condition which obtains in 
Phormosoma shows that the large size of the organs of 
Stewart is not a character of the Hchinothuriide. I need not 
press this point further by urging that this single fact will 
dispose of a good deal of the speculation which made Messrs. 
Sarasin’s essay more than usually interesting. 
Six specimens were dredged at 1000 fath, five of which 
are in the possession of the British Museum ; the colour of 
the test preserved in alcohol varies from lightish yellow to a 
distinct purplish colour; in all cases, unfortunately, the 
spinulation is practically destroyed. 
