82 Papers from the Department of Marine Biology. 



third of the pectorals, and has on each side 10 lamellae furnished with spines 

 in one rank alternately long and short. The mouth is homodont: the teeth 

 of the jaws and vomer are cardiform, but the lower jaw shows on the outside 

 a peculiar character; it projects, is a little enlarged, ends squarely, and bears 

 on each side toward the point an external row of five hooks (crochets) , strong, 

 and pointed, remarkable for their development. The pectorals arise near 

 the opercles, and between their points and the origin of the vertical fins the 

 distance is equal to the length of the head. The unpaired fins are opposite 

 each other and have the ordinary form. They arise at an equal distance 

 from the point of the snout and the end of the tail, the point not being con- 

 sidered. This point, formed of the two middle rays, is 1| times as long as the 

 rest of the caudal, a character very distinctive of this species. The dried 

 condition of my specimen forbids a count of the rays. The color is a very 

 dark blue verging on black. The pectorals are white except at their bases. 

 The two anterior points of the vertical fins are white, as are also the upper and 

 lower edges of the caudal fin, but not the point which terminates it." 



One other reference may be cited just here: Liitken, writing in 1878, 

 speaks of an Echeneis lineaia, a fish identical with Poey's E. sphyrce- 

 narwn, which he found among the collections in the museum of Copen- 

 hagen. This was taken in the South Atlantic from a Sphyrcena 

 barracuda. Liitken thinks that this particular Echeneis is to be 

 found attached only to the sphyrsena. 



Mr. Peter B. Roberts, keeper of the fish market at Key West, Flor- 

 ida, has collected for me a considerable number of small specimens of 

 Echeneis, ranging from about 4 to 7 or 8 inches long. I wrote him 

 asking from what fish these were taken, and his answer was "that the 

 sucker-fish are found on almost every fish in the waters around here, 

 but the greater numbers are found on what are commonly called around 

 here the amber-jack and the black grouper — that is, the smaller ones 

 like you wanted collected." 



I then wrote him that a certain small sucker-fish was thought to be 

 found only on the big barracuda and asked for information on this 

 particular point. Now, Mr. Roberts, by virtue of his position at Key 

 West and his long experience both as fisherman and distributor of fishes, 

 has an exceedingly wide and accurate knowledge of the fishes of that 

 region. He writes: 



"In answer to your questions I would like to state that the fishermen say 

 that there is only one kind of [striped] sucker-fish, and that the small ones 

 are not a distinct kind from the larger ones, but as they grow they naturally 

 cling and stick to the larger fish. The ones found on the barracuda are the 

 same as those found on other fish, the larger they grow the larger the fish 

 they go after. ... I would like to say . . . that I think that they are all the 

 same kind, both big and small, simply growing through the different stages of 

 life." 



After the receipt of this letter the little suckers sent me by Mr. 

 Roberts were carefully examined; 3 were found to have 19 lamella^, 

 9 to have 20, 8 had 21,6 were supplied with 22, 5 with 23, 1 with 24, and 



