336 Dr. Clir. Liitken on Oneirodes Esclirichtii 



The teeth^ as in the allied genera, and especially as in il/e- 

 lanocetiis, have the slender, conical, slightly curved form which 

 is already so well known in Lophius, and they are, as in this, 

 movable, so that they yield before a pressure coming from 

 without, and lie down within the cavity of the mouth ; but, to 

 judge from the figures of M. Johnsonn^ they are comparatively 

 much smaller than in it, which, indeed, is in accordance with 

 the circumstance that the mouth in the northern species is 

 considerably smaller in proportion than in its southern ally. 

 They form a single, not particularly close series both in the 

 upper jaw (on the intermaxillary bone) and in the lower jaw ; 

 in the latter they are on the whole larger, largest (about 

 6 millims.) in the vicinity of the symphysis of the lower jaw ; 

 I count 14—18 in each half of the jaw above, and 15 below. 

 On each of the anterior lateral expansions of the vomer there 

 are two or three teeth ; on the other hand they are entirely 

 deficient on the palatal and pterygoid bones*. The same form 

 of tooth occurs upon the upper pharyngeal bones ; but, as in 

 Ceratias^^ the inferior pharyngeals, the branchial arches, and 

 the hyoid are completely destitute of teeth. The first (outer- 

 most) branchial arch bears no branchiae, and there is no fissure 

 between the fourth and fifth branchial arches ; on the second 

 and third arches the branchial lamellfe are seated in a double 

 series, but on the fourth only in a single one, as in Ceratias 

 and Melanocetus ; and there are thus, in Oneirodes^ as in se- 

 veral other Lophioid fishes, only 2^ pairs of branchise J. Of 



* In Ceratias, as is well known, they are also deficient on the vomer. 

 On the supposed teeth of the palatal and pterygoid bones in Melanocetus, 

 see the postscript to this memoir (p. 343). 



t As Krciyer only mentions pharyngeal teeth in general without re- 

 marking that only the superior ones are present, it is not quite superfluous 

 to call attention to the fact that the two genera also agree in this point. 



X In this respect, therefore, the three above-named Lophioid fishes 

 agree perfectly with each other and with the MaUhcsa-grom^ {Malthcea 

 and Halietdcea). Lophius, as is well known, has three paii-s of branchi^ ; 

 but they are borne on the first, second, and third branchial arches (the 

 fourth being here destitute of branchise) ; and Antemiarius has three and 

 a half pairs of branchite. When Kroyer says (/. c. p. 644) that Ceratias 

 has three branchial arches, all with branchial lamellae in double sei-ies 

 (which is repeated in the Latin diagnosis, p. 648), he is in the wrong ; 

 the third branchia consists only of one row of branchial lamellse, which 

 is the ordinary consequence of there being no fissure between it and the 

 lower pharyngeal bone (fifth branchial arch), which is expressed, but 

 perhaps less clearly, by Kroyer in the words that the third pair of branchial 

 arches " is attached by its inner side." 



The absence of the opercular branchiae does not, indeed, distinguish 

 Oneirodes from the Lophioids most nearly allied to it, but certainly from ' 

 Lophius, in which these organs have generally escaped observation : botln : 

 Kroyer and Valenciennes expressly deny their presence ; and Dr. Giinther ' 

 ascribes this structure to the whole family Pediculati (" pseudobranchiae 



