4 THE POPULAR SCIENCE MONTHLY. 



the fio-ure. The body is an elongated cylinder covered with hard and 

 shining scales closely joined, and leaving as vulnerable points only 

 the throat and gills, the eyes, and the parts just under the pectoral 

 fins. The tail is moderate in size and rounded, the longest rays a 

 little above the middle, so that it is not quite symmetrical. Upon the 

 hinder part of the back is the dorsal fin, and below the dorsal an 

 anal fin, immediately in front of which is the vent or outlet of the 

 alimentary canal. The parired fins, pectoral and ventral, occupy the 

 places natural to them as representatives of the anterior and jjoste- 

 rior limbs of salamanders and alligators. 



The length of the head varies in the difierent species, but, whether 

 longer or shorter, the jaws are furnished with rows of very sharj) and 

 closely-set teeth. The apparent form of these teeth is a simple elon- 

 gated cone ; but it has been shown by Prof. Jefliies Wyman that 

 their surface is really deeply folded, so that a cross-section resembles 

 that of the teeth of the curious fossil Batrachians, called, for that 

 reason, Labyrinthodonts. The eyes are of moderate size. As with 

 ordinary fishes, the ears do not appear externally. The nostrils are 

 two pair of small holes at the tip of the snout, communicating with an 

 olfactory sac on each side; the lining of this sac presents one median 

 longitudinal and many transverse folds. 



The genus Lepidostetis, according to Huxley, has not been found 

 eai'lier than the Tertiary rocks ; although the family Lepidosteidm is 

 represented by more or less numerous genera as far back as the Car- 

 boniferous and perhaj^s (by Cheirolepis) in the Devonian. 



True gar-pikes are not found in Europe, Asia, Africa, or Austra- 

 lia, or in South America ; while in North America they seem to be 

 nearly confined to the Mississippi River and its tributaries, and the 

 Gi'eat Lakes.' 



Prof. Poey has also recorded the existence of a gar-pike in Cuba, 

 a fact which is interesting, not as an indication of "manifest destiny," 

 but as a memorial of the supposed ancient connection between the 

 West India Islands and our continent. None have been found in salt- 

 water, and the writer has no knowledge as to how far they enter the 

 mixed water at the mouth of the Mississippi; but their tenacity of 

 life encourages the belief that they might possibly adapt themselves 

 to the ocean. Their introduction into New England waters would 

 afford to Eastern zoologists the much-desired opportunity of studying 

 their development, of which nothing whatever is known. 



We must now inquire whether there are more than one species of 

 Le^ndosteus. 



Unfortunately, this question involves several otliers. For the 

 genus Lepidosteus, established by Laccpede for the single species 



' A few examples have been taken in Cayuga Lake, in Central New York, having 

 probably entered by the canal at iti3 northern end ; it is said to occur in the Susque- 

 hanna River, Pennsylvania. It is lately reported that a species has been found in China. 



