694 TELEOSTEI CHAP. 
characters have, however, not yet been tested on a sufficient 
number of the very numerous forms grouped under Cottidae, 
some of which I have already transferred to the Comephoridae. 
SYNOPSIS OF THE FAMILIES. 
I. Head not completely cuirassed. 
A. Ventral fins not widely separated ; none of the pectoral pterygials in 
contact with the clavicle. 
Two nostrils on each side; basis cranii double; gill-membranes free from 
isthmus . : : ; . - 1. Scorpaenidae. 
A single nostril on sap Gls basis cranii double ; gill-membranes free from 
inane : ; : , ; . 2. Hexagrammidae. . 
Two nostrils on eck side ; basis cranii simple; gill-membranes free or 
narrowly attached to isthmus : ' : . 3. Comephoridae. 
Two nostrils on each side; basis cranii simple; gill-opening narrow, above 
base of pectoral : ‘ : . 4. Rhamphocottidae. 
B. Ventral fins, if present, a Ww idely separated ; one or several of the 
pterygials in contact with the clavicle. 
Ventral fins distinct ; gill-clefts wide . : . 5. Cottidae. 
Ventral fins united into a sucking pee gill-opening narrow, above base of 
pectoral , : sy! ea: Cyclopteridae. 
C. Ventral fins w idely cpuratede none of the pterygials in contact with 
the clavicle. 
Ventral fins behind base of pectorals ; praecaudal vertebrae without trans- 
verse processes : ; . 7. Platycephalidae. 
Ventral fins a little in fod of eee of pectorals ; praecaudal vertebrae with 
transverse processes : 3 5 . 8. Hoplichthyidae. 
II. Head completely phipased 
Ventral fins narrowly ee ; no pectoral appendages ; pterygials short 
and broad. ; : . 9. Agonidae. 
Ventral fins widely sonata 2 or 3 iow ermost rays of pectoral fin detached 
as feelers ; pterygials short and broad 4 . 10. Trighdae. 
Ventral fins narrowly separated ; pectoral fin divided into two portions ; 
pterygials elongate . a : P . 11. Dactylopteridae. 
Fam. 1. Scorpaenidae.—Head not or but incompletely 
cuirassed, usually with spines; basis cranii double; parietal bones 
often meeting on the median line, over the supraoccipital; two 
nostrils on each side. Gill-membranes free from isthmus; gills 
34 or 4; pseudobranchiae present. Vertebrae 24 to 37, the 
anterior praecaudals with sessile ribs bearing epipleurals, the 
posterior with transverse processes, often directed downwards, or 
forming haemal arches, bearing the rib and the epipleural. _Post- 
temporal more or less distinctly forked, more or less firmly anky- 
losed to the skull; scapula and coracoid well developed, in contact 
with each other or separated by cartilage; pectoral rays inserted 
