46 
REVISION OF THE 
KEY TO THE GENERA OF THE BATRACHOIPIDyE. 
a. Spines solid, without poison-sacs. 
b. Body covered with small cycloid scales ; vertebras 12 + 17 = 29. 
c. Three dorsal spines. 
d. Dorsal rays 25 to 29 ; anal 21 to 26 ; no axillary pore... i. Batrachoides.* 
dd. Dorsal rays 17 to 21 ; anal 14 to 17 ; an axillary pore... ii. Halobatrachus.f 
lb. Body scaleless. 
e. Dorsal spines three ; no canine teeth. 
/. An axillary pore ; teeth uniserial, strong and conical. 
g. Dorsal rays 26 to 28 ; anal 22 to 24 j vertebrae 12 + 22 = 34. 
iii. Opsanus. 
gg. Dorsal rays 18 to 22 ; anal 15 to 18 ; vertebras 9 + 18 = 27 or 
12 + 17 — 29 ■ iv. Batrachomceus. 
ff. No axillary pore. 
h. Dorsal rays 28 to 30 ; anal 22 to 24 ; teeth short and very blunt ; 
vertebras? ... ... ... ... ... ... v. Marcgravia. 
hh. Dorsal rays 19 to 22 ; anal 15 to 18 ; teeth in narrow bands, acute 
and cardiform ; vertebrae 10 + 17 = 27 ... vi. Coryzichthys. 
ee. Dorsal spines two ; canine teeth present on the vomer ; vertebras 
12 + 31 = 43 vii. Porichthys. 
aa. Spines hollow, each connected with a poison-sac. 
i. Dorsal spines two. 
j. Dorsal and anal fins free from the caudal ..viii. Thalassophryne. 
jj. Dorsal and anal fins fully united to the caudal ix. Dcector. 
ii. Dorsal spines four x. Thalassothia, 
The new genus Halobatrackus is here proposed to accommodate 
JBatrachus didactylns and its allies from the Eastern Atlantic, and 
bears the same relationship to Batrachoides as Opsanus does to Marc- 
gravia and Batracliomoeus to Coryzichthys. 
I. BATRACHOMCEUS g en . no v. 
? Pseudobatrachus Castelnau, Res. Fish. Austr., 1875, p. 24 (striatus). No 
description. 
Body depressed anteriorly, without scales. Three inconspicuous 
lateral lines, the pores without cutaneous appendages. Mouth with 
wide horizontal cleft, the lower jaw projecting ; maxillary extending 
to below the hinder border of the eye. Jaws with a single series of 
conical teeth, those of the mandible much the stronger ; usually a 
few smaller teeth at the symphysis in front of the functional series : 
vomerine and palatine teeth strong, arranged in a continuous band, 
the former sometimes biserial. Eyes of moderate size, superolateral. 
Opercle with two strong spines ; subopercle normally with two 
* The italicized genera are exotic. 
f aAs, gen. aX6<s, sea ; fidrpaxos, a frog. 
