58 MR. T. J. PARKER ON THE INTESTINAL 
ture which must offer an immense amount of resistance to the passage of the intestinal 
contents, and, of course, making a decidedly greater proportional increase of surface 
than in any of the cases recorded of the Ray. The difficulty of cleaning out the intes- 
tine afforded a good criterion of the forms of these points; the finely divided contents 
stuck so tightly between the successive “cones,” that a stream of water was often quite 
insufficient to dislodge them. In fact the chyle (if one may apply the term to what 
rather resembled fine mud) completely filled up the whole available space in the intes- 
tine, so that, although the animal was preserved entire in spirit, the gut and its valve 
were in as good a condition for examination as if the former had been carefully emptied 
and distended with spirit while fresh. The pyloric valve was very perfect, having the 
form of a short conical tube projecting into the bursa entiana, with a very small aper- 
ture at its apex. ‘This, of course, brought about the result referred to, that only finely 
divided matter could find its way into the intestine. 
Another point I may mention about this specimen is the great thickness of its walls 
at the posterior end; the thickness was actually greater than the diameter of the 
lumen.at that part. This may have been a mere individual abnormality; but it seems 
not impossible that this increase of muscular substance had relation to the great force 
necessary to drive on the contents in a gut with so peculiar a spiral valve. 
In a smaller specimen of the same species there were eight turns to the valve, of 
which the first five had a forward, the last three a backward direction; so that the 
valve was intermediate in character between C and D. 
§ 15. In Notidanus I found the valve to have twenty turns, and to be very much 
what fig. 1, Pl. X., would be if its posterior turns reached the centre—that is, inter- 
mediate between B and C, and approaching more nearly to the former. ‘The pylorus 
is like that of Scylliwm, projecting into the cavity of the intestine as a short tube with 
a narrow aperture, and forming a highly perfect valve. 
§ 16. In Cestracion philippi there were eight turns to the valve!; these, again, were 
intermediate between B and C, but approached more nearly to the latter type than in 
Notidanus. The pylorus was remarkable, being very wide and quite devoid of any well- 
marked valvular arrangement. In correspondence with this, entire Cephalopods, par- 
tially digested, were found in the intestine. 
§ 17. In Chimera monstrosa (Pl. XI. fig. 6) I found a valve of only three and a 
half turns, remarkable from the fact that the attached edge did not form a regular 
spiral, but for a part of its course (namely, during the first turn) formed a slightly 
Sinuous antero-posterior line. In consequence of this, the second compartment of the 
intestine was fully half as long again as the bursa entiana. 
§ 18. The only other Elasmobranchs which I have been able to examine are Zygena 
malleus and Carcharias lumensis, two of the genera which, instead of a spiral valve, 
* Duméril (‘ Ichthyologie générale’) found the same number in this species. 
