LEPISOSTEIDA. — XXIL. 35 
and vent. D. 42, A. 27. Changes greatly with age, the young 
with sharp snout and very rough shields, and the spines strongly 
hooked ; the adult with blunt snout and small smooth shields, most 
of them finally lost. lL. 6 feet. Miss. Valley, Great Lakes, and 
N., abundant, ascending rivers in spring, but not entering the sea. 
(Lat., ruddy.) 
cc. Last dorsal shield very small, less than half length of next the last ; 
dorsal shields 10 to 12. 
43. A. brevirostrum Le Sueur. Snout short, bluntish, much 
shorter than rest of head. Dorsal shields 11; lateral, 30 ; ventral, 9 ; 
one shield between anal and vent. D. 43, A. 24. N.Y. to Fla., 
scarce. (Lat. brevis, short; rostrum, snout.) 
OrverR IX. GINGLYMODI, 
This order, defined on page 25, contains but one family among 
recent fishes, although it has many allies among extinct forms; 
(yiyyAvpos, hinge; ddovs, tooth.) 
Famity XXII. LHEPISOSTHIDA). (Tue Gar-risuEs.) 
Body subcylindical, covered with rhombic enamelled “ganoid ” 
scales, imbricated in oblique series which run downward and back- 
ward. Jaws both elongate, the upper always projecting; pre- 
maxillary forming most of upper jaw, the maxillary transversely 
divided into several pieces; lower jaw formed much as in rep- 
tiles; both jaws with an outer series of small teeth followed by one 
or two series of larger teeth of peculiar structure; close-set, rasp- 
like teeth on jaws, vomer, and palatines; tongue toothless, broad, 
emarginate; external bones of head very hard, rugose. Eyes 
moderate; nostrils near end of snout; pseudobranchize present, 
besides an opercular gill; B. 3; no spiracles; air-bladder cellular, 
joined by a glottis to the ceesophagus, resembling the lungs of rep- 
tiles, and used in respiration. Fins with fulecra; D. short, nearly 
opposite A.; tail heterocercal, produced as a filament in young; 
vertebre with ball and socket joint, as in reptiles; pyloric cceca ~ 
many. One genus now living, with 3 or 4 species. Singular fishes, 
inhabiting the lakes and larger rivers of Eastern North America. 
The species are extremely variable in coloration, length of snout, 
proportions, etc., a fact which has given rise to a multitude of use- 
less specific names. 
32. LEPISOSTEUS Lacépéde. 
(emis, scale; daréov, bone; more correctly written Lepidosteus, 
but the above is the original word.) 
a. Beak long and slender, the snout more than twice length of rest of head. 
44. L. osseus (L.). Common Gar-Prke. LoneG-Nosep Gar. 
Biiu-FisH. Olivaceous; vertical fins and posterior parts with 
