45 



The Pallitd Teutarlex roTiiul the niaiitlo edge liave 

 ivlreudv been mentioned in general terms, a]id it lias l)een 

 said that they are of two kinds, large and small, of 

 similar structnre. A large tentaele ean extend as mneh 

 as ^ of an inch beyond tJie mantle edge. The surface of 

 a tentaele presents a number of fine encircling ridges, 

 and, by the action of muscle strands, it can be reiiacled 

 info a ])it, when its surface is thrown inio jirominent 

 circular folds. The pits for the large tentacles are 

 situated further ventral tlian those for the small ones 

 (figs. 8 and 24). Tlie tentacle (fig. S) is covered by 

 columnar epithelium made up of two kinds of cells 

 resting on a basement membrane: — {a) Relatively broad 

 goblet cells with a basal nucleus ; and (h) Sensory cells 

 which are slender, and narrowest in the middle where the 

 nucleus is situated. The outer end bears a number of 

 stiff sensory processes, so that the cell is of the brush lypf 

 (pinselzeUe) described by Flemming. 



Underneath the basement membrane scattered ganglion 

 cells and nerve fibres can be made out ; the latter converge 

 to the axis of the tentacle, where they form a nerve 

 which is connected with the peripheral part of the nervous 

 network of the mantle. At the points of fusion of the 

 tentacle nerves with this network a tew ganglion cells are 

 found. Wliere a. tentacle is retracted its nerve is thrown 

 into a coil. 



lieneath the epithelium of the tentacle is a fairly 

 continuous sheath of longitudinal muscle fibres, <li(> 

 majority o4 which are inserted into tlie tip, tliough some 

 end at the basement membrane. Most of them collect at 

 tlie base into two bands which run into the mantle in 

 different directions, those of a laterally placed tentacle 

 l)eing relativelv more or less anterior and posterioi', 

 thouah not necessarilv in Ihe same horizontal iilane. Tlio 



