109. LIPARIDID.E - AMTTRA. 7o9 



<t. Ventral disk entirely \vautiug. (AmitrinCB.) 



b. Lower jaw included ; skin thin, lax .............................. AMITRA, 3i~ 



CHI. Ventral disk present. (Liparincp.) 



c. Ventral disk very small, under the head, the vent close behind it; lower jaw 

 projecting; skin lax, thin ................................. CAREPROCTUS, 3y:>. 



cc. Ventral disk well developed ; vent well behind head ............ LIPAKIS, 394. 



392. AMITRA Goode. 



(Goode, Proc. U. S. Nat. Mns. 18SO, 478: type Amitra lipartna Goode.) 



Body elongate, attenuate backward, covered with lax, smooth, slimy 

 skin, which is separated from the body and fins by a filmy mucous inter- 

 tissue. Dead small, thick, convex between eyes; snout convex, pro- 

 truding-; mouth small, horizontal, the lower jaw included; teeth small; 

 eyes lateral; gill-openings restricted to small slits above the base of the 

 pectorals, covered by the very small opercle; no barbels; dorsal and 

 anal fins many-rayed; dorsal continuous, almost concealed by the skin; 

 the spines scarcely different from the soft rays; anal similar to dorsal; 

 both connected with the caudal, which is pointed; no trace of ventral 

 fins or sucking disk; pectoral fin very broad, procurreut, its lower rays 

 inserted nearly under the eye, the fin emarginate; vent well behind 

 head. One species known; its position intermediate between the Cot- 

 tidce (Cottunculus, Psychrolutes) and LiparuUflic, two groups much more 

 intimately related than most writers have conceded.* (, without; 

 stomacher.) 



1129. A. laparina Goode. 



Yellowish white, dusky toward the tail and front of head ; perito- 

 neum black. Body posteriorly compressed, the tail very thin; eyes 

 half width of interorbital space, 5 in head; upper lip with pores. Dor- 



. - _ -- _ _^ - ~ --- 



*I should put the family of Gobiesocidce far away, at least a suborder off, from the 

 (lyclopteridce and Liparididce, which are far more closely united to the true Coilitlu . 

 represented by Cottus and Hemilriplerus, than to either the Gobiesotddce proper or to th<- 

 Gobies and Bleunies. In fact, Llparls has as close affinities, as shown by its skeleton, 

 with Cottus and Hemitripterus as with Cyclopteras ; and we have in the three groups. 

 represented by Cottiis, Liparls, and Cydopterus, well-inarked families of the same sul-- 

 order. The only character by which the Ci/clopteiida; and Lipurldidcc are closely united 

 consists in the peculiar formation of the ventral disk by the union of the ventral tins: 

 but as this structure is simply brought about by the modification of the rays in a 

 manner common to the several genera, and not by any marked anatomical difference iu 

 the structure of the same fins in Cottus, I can only look upon it as a generic character 

 common to the known representatives of both families of Cyelopteridce and Liparididir ; 

 and the discovery of a representative of either family with ventral tins of the ordinary 

 form would not necessitate the establishment of a family for its reception, as in that 

 cai,e we should simply consider the structure as of generic value. (Putnam, 

 Ani. Ass. Adv. Sci. 1673, 337.) 



