MONOGRAPH OF THE FRESH WATER Til. 
The numbers 8’, 732 and 73 we have added to the series; 72 is called supratemporal by Professor 
76 
Owen. 
Fig 
Fig. 10—13. 
Fig. 14—17 
Fig. 18—21 
Fig. 22—25 
Fig. 26—29 
Fig. 30—32 
Fig. 833—35 
Fig. 836—88 
Fig. 89—41 
Fig. 42. An 
Fig. 43—45 
Fig. 46—48 
nm s—neural spines. n’—neuro-caudal plate. 
7 n—interneural spines. }/—heema-caudal plate. 
dn—dermo-neural spines. dn’—caudo-dermo-neural spines. 
h s—heemal spines. pl—pleurapophysis. 
i h—interhzemal spines. 
dh—dermo-hzemal spines. 
a represents the tenth vertebra, with its pleurapophyses and pelvic appendages below. 
B is an anterior thoracic vertebra. 
8 is a group of five vertebrae, two pelvic and three caudal. 
ail belong likewise to the caudal region. 
a) 
ic. 6—9. Skull of Cottus viscosus; Fig. 6 from above; Fig. 7 from below; Fig. 8 in profile; and Fig. 
9 from behind. 
Skull of Cottus Franklinti; Fig. 10 from above; Fig. 11 from below; Fig. 12 in profile ; 
and Fig. 13 from behind. : 
. Skull of Cottus Wilsonii; Fig. 14 from above; Fig. 15 from below; Fig. 16 in profile ; 
and Fig. 17 from behind. 
. Skull of C. Richardsonii; Fig. 18 from above; Fig. 19 from below; Fig. 20 in profile ; 
and Fig. 21 from behind. 
. Skull of Triglopsis Thompsonii; Fig. 22 from above; Fig. 23 from below; Fig. 24 in 
profile; and Fig. 25 from behind. 
. Skull of Acanthocottus virginianus ; Fig. 26 from above; Fig. 27 from below; Fig. 28 in 
profile; and Fig. 29 from behind. 
2. Vertebrae of Acanthocottus virginianus ; Fig. 30, thoracic, with its pair of pleurapophyses or 
ribs; Fig. 31, pelvic, with its pair of pelvic appendages; Fig. 32, caudal. 
. Encephalon of Acanthocottus virginianus ; Fig. 33 from above; Fig. 34 from below; and 
Fig. 35 in profile. 
. Encephalon of Triglopsis Thompsonti, twice the natural size; Fig. 36 from above; Fig. 37 
from below; and Fig. 38 in profile. 
. Encephalon of Cottus gracilis, twice the natural size; Fig. 39 from above; Fig. 40 from 
below; and Fig. 41 in profile (under the name of C. gobioides on the plate). 
imperfect sketch of the encephalon of C. gobioides, twice the natural size, seen from above 
(under the name of C. gracilis on the plate). 
. Encephalon of C. viscosus, twice the natural size; Fig. 43 from above; Fig. 44 from below ; 
and Fig. 45 in profile. 
. Encephalon of Acanthocottus variabilis; Fig. 46 from above; Fig. 47 from below; and 
Fig. 48 in profile. 
