cclvi BRANCHiosTOMiDa:. PISHES. Fbesh-wateb Fishes. 
Pamii.y— MYXIN lDiE . 
in European waters, in India, and on the coast of 
South America. 'I’his form is supposed to be a relic 
Named from the typical g-eniis, Myxine. 'I'lie 
or surviving type of an ancient class, which was 
species are lon'>' and slim, naked and slimy, having- 
probably very plentiful in the distant past. 'I’he 
six branchial sacs on each side. Prof. P. W. Put- 
brain is exceedingly simple, not lobed largely as in 
nam, an American naturalist, regards the varieties 
other vertebrates. 'I’he skull is undeveloped, and 
as belonging- truly to one species. “'I'he egg-s, from 
there are no rudiments of an auditory apparatus. 
ten to eigliteeu in number, are comparatively very 
'I’he skeleton is represented by a simple notochoi-d. 
large. Wlien deposited they are encased in an elon- 
or embryonic backbone, which is not divided into 
gated, oval, hairy shell, provided at each end with a 
vertebrae, and has no ribs or other appendages. 'I’he 
tassel of tubular filaments.” They prefer muddy bot- 
circulating system is very simple, the heart being- 
toms, and feed mostly upon dead animal matter. 
simply tubular, and not divided into distinct chain- 
HOG-FISH [Myxine glutinosa, Linn.), called, also. 
bers ; hence the name of the class. Slender-hearted. 
Sucker and Slime-fish, is found from the Polar re- 
LANCELET [Branchiostoma carihmum, Sunde- 
gions to Cape Cod. Gill records it as not definitely 
vail ). — Pound from Hatteras southward. Amphi- 
settled as to species. 
Pamily— BRANCH lOSTOMlDAi. 
oxus (sharp at both ends) was the generic term 
formerly applied to this species. Little is known of 
the habits, but the position of it in the system of 
Although included by Gill in his .£'asi Coast Fishes, 
nature is exceedingly interesting. Dorpat, Ray, Hux- 
this family is now referred to a separate class, which 
ley and Lankester have recorded very much that is 
has been named Leptocardia. Jt is the lowest class 
valuable aiid new concerning its anatomy. Prof. G. 
of vertebrates. 'I'he family embraces but one genus. 
Browne Goode dredged some specimens of the Am- 
'I’he species are yet in doubtful relations ; one only 
phioxus in Bermuda waters, which were found em- 
is known to our coast. Representatives are found 
bedded in sand. 
FISHES OF THE FRESH- WATER STREAMS AND LAKES. 
Pamily E rHEOSTO.MlDAi; [Darters) are small 
Rainbow-fisii and Blue Johnny, is abundant in the 
Presh-water Pishes, closely allied to tlie Perches. 
Mississippi Valley, and is the most brilliantly color- 
'I'he two dorsal fins are usually connected by a mem- 
ed of all. Other species are: P. spectabilis and P. 
brane at the base, the second dorsal standing high. 
zonalis, inhabiting Indiana and 'I’ennessee ; Pusi- 
and with considerable breadth ; both dorsals are 
FORM Darter (Boleichthys fusiformis, Jordon), 
flanked with one or two sharp spines. 'I’he most 
found in the Charles River, Massachusetts. Other 
brilliantly colored fresh-water Pishes are of this 
species are : B. erochroiis (red-sided). New Jersey, 
group. 'I'liere are ten genera and about thirty spe- 
and B. exilis, Girard (slender-sided), abundant in 
cies; all found in the United States and Mexico, 
clear brooks in the North-western States. Sand 
east of the Rocky Mountains. It is said that all of 
Darter (Pleurolepis pellucidus, Ag.) inhabits the 
the genera may be found in the same stream in some 
sandy streams of the Ohio Valley. 'I’his is regarded 
portions of the Mississippi Valley. 'I’he habit of 
as one of the most interesting- of our Pishes. It has 
many of this family is to prefer clear-running water, 
a habit of plunging bodily into the soft, sandy bot- 
lying on the bottom, concealed under the stones. 
tom, where it lies indefinitely, with snout and eyes 
'I’hey are never seen floating- or swimming leisurely. 
only visible. We have witnessed this curious habit 
as most other- Pishes do, but, when disturbed, they 
of seclusion in the New York Aquarium. 'I’essel- 
dart forth from the hiding-place with a quick stroke 
LATED Darter (Bolosoina olmstedi, Ag.) ; abundant 
of their powerful wide pectoral fins, and as suddenly 
from New England to Wisconsin. A variety, called 
halt and settle down again, resting upon the extended 
atroinaculata, is known. B. effulgens (Little Johnny 
ventrals and anal. 
or Slim Darter) is abundant in the Eastern States 
LEAST DARTER [Microperca punetulata, Putnam). 
and west of the Alleghanies. Elheostonia (Black- 
— A small greenish-olive species, found in the West- 
sided Darters). 'I’hree species are recorded under 
ern and Southern States. Length, one and a quarter 
this genus. One found in the Great Lakes is said to 
inches. Pan-tailed Darter (Catonotus flabellatus. 
be one of the prettiest. 'I’he others are found in 
Putnam), found in the great lakes and streams from 
l-’ennsylvania and the Western rivers. Hypohomus 
New York southward and westward ; an abundant 
(Orange-sided Darters). One, a large species, is 
species. Striped Darter (G. lineolatus) is from the 
known. Diplesium (Green-sided Darters) is repre- 
same localities and northward. 'I’rout-darter, or 
sented by two species. Percina (Log Perches). 
Blue-breasted Darter (Nothoiiotus niger, Jordon) is 
Species of this genus are called, respectively. Loo 
regarded as one of the handsomest of native Pishes, 
Perch, IIog-fish and Jack-pike. 'I’hey are abun- 
and inhabits the waters of the Ohio Valley ; length. 
dant in the great lakes and streams of the West. 
two and one-half inches. Dotted Darter (N. punc- 
One only is known in North America, viz., P. capro- 
tulatus), found in Missouri and Arkansas. Blue 
lies (Raf.), Girard, and is the largest of the Darters, 
Darter (Poecilichthys ceruleus, Agassiz), called 
reaching- a length of eight inches. 
