CRTPT0PHIA1.US MINUTUS. 577 



so that the cirri with their pedicels (coloured purple like the 

 exposed labrum) can be wholly protruded out of the sack 

 and shell-cavity. The three cirri no doubt can be separated 

 a little from each other, both transversely and longitudinally; 

 and according to analogy, the two rami of each cirrus can 

 likewise be separated : there are, also, muscles for moving 

 the two segments of the pedicel of each cirrus ; and other 

 muscles run up the many segments of the rami. We have 

 seen that the great lancet-formed appendage of the labrum, 

 laterally fringed with fine hairs, can be erected ; and I do 

 not doubt that the prey when entangled by the expanded 

 cirri, is borne against this appendage, and is then, by the 

 retraction of the thorax, dragged down its smooth surface 

 to the mouth, where it is seized by the mandibles and 

 maxillae, which lie like a trap at the bottom of an inclined 

 and moveable plane. 



Alimentary Canal. — The oesophagus is long ; it runs 

 backwards from the mouth and then downwards ; at its 

 lower end, where it enters the stomach, the part, which in 

 other cirripedes is expanded and bell-shaped, is modified 

 in a most singular and quite peculiar manner; for the 

 lower part of the oesophagus, after widening a little, 

 becomes converted into what appears at first like a square 

 box, youths of an inch across. This box is really deeply folded 

 (see diagram, PL 24, fig. 11) into six longitudinal ridges and 

 hollows : two of these hollows, facing each other, are wider 

 than the others, and when the organ is dissected out of the 

 body, it generally lies (fig. 10) with one of these faces exactly 

 over the other, the narrower lateral folds being thus hidden, 

 and the whole consequently appearing like a simple square 

 box with concave sides. But when a section is made, or the 

 lower open end is turned upwards, we see that the organ is 

 six-rayed and elongated, with the longer axis standing 

 parallel to the flattened sides of the animal's body. The 

 edges of the folds are formed of yellowish, thickened mem- 

 brane, with a sinuous or beaded outline, which serve to 

 strengthen the ororan. Internallv, the two broad concave 

 sides are armed, in their upper inwardly prominent (fig. 12) 

 part, each with a disc, T( ^otbs of an inch in diameter, crowded 

 with short, thick, brownish, inwardly projecting teeth. The 



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