OBSERVATIONS ON THE NATURAL HISTORY 

 OF POLYODON SPAT HULA 



Charles R. Stockakd 



During the springs of 1904 and 1905 1 visited the regions in which 

 Polyodon attains its largest size and occurs in greatest abundance. 

 I had been aware for several years of the existence of this fish in 

 great numbers in the lakes bordering the lower Mississippi River. 

 On mentioning this fact to Professor Bashford Dean, lie suggested 

 to me the desirability of visiting these lakes with the ol)|ect of 

 obtaining the eggs and developmental stages of this j)ecnliar fish. 

 My best thanks are due Professor Dean for this .snggt\stion. and 

 for placing at my disposal during both years the Dyekman Fund 

 of the Zoological Department of Columbia I'ni\(>rsity with which 

 to defray the exj)enses of the trips. 



Most vertebrate enibryologists and particularly those familiar 

 with the developTiient of the ganoids will admit, I believe, that a 

 knowle<lge of the (h-vek>i.nient of Polyo.lon i- oMvatly -lesire.L 

 ^rhe ganoi.U at lucent furnish an ahnoM eoniplefe an.l one of the 

 most inMnietiv<- eon.pai atixe enibn ok)u-i<'al .eri,... 'I'he MTie. 



n>ent of 'either luetnher (4" the order Sehieho>i.,nii. This order 

 comprises onlv tuo .|H-ei<... PnlinnUni spalhuht an.l P.-^rphuru.^ 

 gladius. The former i. found in tli.^ Mis.i..i,>i,i Hiv.M- and its 

 tributaries; the latn^r i^ known <.nb in M.me of the rivers of China. 

 Thusthex haxe a <hMMde<livdis,-ontinnonsuvograpliI( al distribution. 

 T spent from Manh tirst to April fii'teenth. in (on<.,rdia 



the' W hite Miver in Arkansas. Dnrimr this entire tinie ell'orts 

 were made to obiain spuunin- rolwulon. Ahho.ml, unfortmiately 



the tln-ee mouths on the kik.'s an<l I'iwrs u her.- this (ish is s,, 

 abundant, in making „kui> ..bsrrv ati.)ns on its habits. The 

 present pap<M- contains a brief aecotint of the behavior of the fish 

 753 



