4 BROOKLYN -Ml'SEUM SCIENCE Bl'LLETIN 3. I. 
quiet, .s])arklin,u; summer sea, and then slipi^iiy; out of sio^ht not to ap])ear 
a,s^ain, suggests an evil spirit. His leering, chinless face, his great 
mouth with its rows of knifelike teeth, which he knows too well how to 
use on the fisherman's gear, the relentless fur\ with which, when his 
last hour has come, he thrashes on deck and snaps at his enemies ; his 
toughness, his brutal nerveless vitalit>' and insensibilit\' to i)h\sical in- 
jur\-, fail to elicit the admiration one feels for the dashing, brilliant, de- 
structi\'e, gastronomic bluefish, tunny, or salmon. Probabl\- few swim- 
mers have actuall\- met in him their fate, InU doubtless man>- a poor 
drowned sailor has there found his final resting place. 
ARTIFICIAL KEY 
I. (lill-.slits more or less lateral, not strictly on the ventral surface. 
a. l'"ront of pectoral fin not separated from the neck b}- a deep notch. 
/). First dorsal fin several times longer than high. 
Ilsnufo/riakis iiiicrodoii 
b' . First dorsal fin little, if any, longer than high. 
( . .Anal fin present. Dorsal fins without spines. 
(/. Caudal peduncle without a keel in the center of its side. Caudal fin not 
lunate. 
e. Teeth without basal cusps. 
/". Caudal fin moderate, much shorter than head and Ijody together. 
i,'. Head normal in form. 
//. Teeth small and blunt. A small slender shark, flattened l)elow. 
M usUiiis caiiis 
li' . Teeth larger, sharp, more or less pointed. 
/. Angle of mouth without a well marked groove extending 
along one or both jaws. Teeth erect or moderately oblique. 
j. Teeth similar in both jaws, broad, coarsely serrate, with 
oblique tip and an acute notch below it. .\ large, usually 
spotted shark. 
(iaicoccrdo fii^riiiiis 
J' . Teeth not as aljove. 
/>•. Teeth with more or less serrate edges. 
/. I'irst dorsal fin opposite or behind the center t)f the 
space between the pectoral and ventral fins. A 
large slender species. 
/'lioitacc g/aiica 
I'. Dorsal fin before the center of the space between })et'toral 
and \entral fins. 
III. I'pper teeth broad, triangular, (|uite different from 
the lower, which are narrow on broader l)ases. 
;/. Dorsal fin higli and rather ]jointed. 
C 'ari/iar/iiiiiis iiiilhiTii 
