GAR-PIKES, OLD AND YOUNG. 5 



osseus, has since been subdivided by some authors into Lepidosteus, 

 Cylindrosteus, and Litholepis, or Atractosteus ; and nearly forty spe- 

 cific names have been applied. One of these, Sarchirus, merely de- 

 notes the lobed state of the pectoral fin of the young gar (as will be 

 shown further on), and most of the others seem to be based upon 

 individual or geographical variations. Much more remains to be 

 learned before the exact number of species can be ascertained; mean- 

 time, we may safely admit the three following : 



L. osseus, the bony gar, having a long and narrow snout, and 

 rarely attaining five feet in length ; L. platystomus, the short-nosed 

 gar, with a short and broad snout, as the name implies ; and X. ada- 

 mantinus, the alligator-gar or diamond-gar, with a short and wide 

 snout, but attaining a greater size than the other two, and more com- 

 mon in the southern part of the Mississippi Valley. Probably the 

 careful comparison of many individuals will oblige us to admit one or 

 two additional species. 



Notwithstanding, however, the peculiarities by which several of the 

 species of Ziepidosteus may be distinguished, so many and so obvious 

 are the features which unite them together, and separate them from 

 all other fishes, that they are recogtiized by all as belonging together, 

 just as are the catfishes, the suckers, or the sturgeons. 



Moreover, their internal structure, so far as it has been ascer- 

 tained, presents a remarkable uniformity, whence we may infer that 

 there is no important difierence in their functions or habits, except- 

 ing in so far as may depend upon their circumstances, their food, etc. 

 It is desii'able to ascertain the extent of this variation, by accurate 

 observation of carefully-determined examples, but on the present 

 occasion we must be content, although unwillingly, with the assump- 

 tion that what one gar has done another gar can do.' 



Like most other New England zoologists, the writer had been long 

 obliged to content himself with dead gar-pikes, and with the some- 

 what unsatisfactory figures and descriptions which occur in a few 

 zoological works. He had gained some more vivid impressions from 

 the words and blackboard sketches of him who regarded " the estab- 

 lishment of the order of Ganoids as the most important advance which 

 he had brought about in ichthyology." "^ 



But even these privileges only increased the desire to behold the 

 gar alive and active, and to realize the delight expressed by the great 

 teacher when first enabled to observe them ujDon his journey to Lake 

 Superior. 



' Unwillingly, because all such assumptions are very undesirable. There have proved 

 to be exceptions to nearly all general rules, whether of structure or of functions, as is 

 shown in a paper by the writer, entitled " Is Nature inconsistent ? " (The Galaxy, April, 

 1876.) 



' Although most other zoologists have differed with Agassiz respecting the limits of 

 the group, the name has been generally retained. 



