26 SEA-SIDE STUDIES. 



of an inch high ; and note how the caudal fin, instead 

 of being a climax to the tail, as in other fishes, forms 

 a delicate ridge running all down the back. What 

 a delicate Quaker brown the colour is, and how the 

 transparency of the tissues allows us to see the pulsat- 

 ing heart ! I hope we shall be able to keep it alive ; 

 it will be the cynosure of our collection. 



Meanwhile one of our party who has been ferreting 

 everywhere, is now crouching in a pool, and presently 

 calls to us to come and see a Terebella (Plate VII., 

 fig. 1). In thre^ rapid strides we are there, crouch 

 down, look where he jDoints, and see — nothing. 



" Impossible ! Don't you see long waving threads, 

 like minute worms?" 



" Yes, I see threads, but that's all." 



" That is the Terebella. His body is snug in the 

 mud, and he pokes his long arms out in this way for 

 some purpose or other, to me unknown." 



" Perhaps for respiration ? " 



""Why do you say that?" 



" Because it's safe. Whenever zoologists don't know 

 the function of an appendage, they are pretty sure to 

 say it's connected with respiration ; every unknown 

 spot is an eye, every appendage a gill, or subsidiary 

 to gills ! However, the Terebella has already been 

 credited with branchial tufts, in the shape of smaller 

 and redder little worms beneath the tentacles ; so never 

 mind about function * — get the animal, which I have 

 never seen out of books." 



* See the next Chapter for an elucidation of this point. 



