60 



PROCEEDINGS OF THE NATIONAL MUSEUM. 



G<tsterostcvs microceplialus Girard, Proc. Acad. Nat. Pci. riiila., 1S54, j). irj."^; 

 Kaweah II., Tulare T^akc; lialf-maikvl form. 



^rV(,s-/r/v(,s7('»,s' j>/r/;('/».s (i IRAKI), Proc. Acad. Nat. Sci. I'liila., isr)4, \>. 147: Presidio; 

 lialf mailed. 



Gasterosiens inopinatH.-< (\\R.\Hi), Proc. Acad. Nat. Sci. I'liila., 1854, ]>. 147; Presi- 

 dio; half mailed. 



Gasterosteus 'pngetti (tirakd, Proc. Acad. Nat. Sci. Phila., ISoi;, p. i;i,5; Fort 

 Bteilacooni, Washington; half mailed. 



The following" description is tuken from u specimen So nnn. long 

 from Ugo, northwest »Tapan: 



Head 3i; depth 4i; eye 3|. Dorsal 11-1, 13; anal 1, 1(». Body slender, 

 compressed; head small and pointed; mouth obli(iu(\ maxillary not 

 reaching eye', caudal peduncle depressed, keeled. Processes from 

 shoulder girdle slightly divergent, leaving a narrow, naked area on 

 breast; naked area in front of pectorals equal to length of snout. 

 Dorsal spines long and slender, the length equaling distance from 

 snout to pupil ; third dorsal and anal spines very small, curved; ven- 

 tral spines long, slender, as long as snout and eye, or even longer in 

 some specimens; serrate at ])ase and Avith basal cusp; ventral plate as 

 long as spine in many specimens, narrow, the greatest width 3i in 

 length. Lateral armature complete, the plates gradually reduced in 

 size posteriorly, forming a distinct caudal keel. Dark grayish or blu- 

 ish black above, silvery below, witii a few dark punctulations, thickest 

 on caudal peduncle and near tip of ventral spines. Alaska, Kam- 

 chatka, and Japan. Very abundant northward; the mailed form rarely 

 or never entering fresh water. 



We have also marine specimens from Kushiro and northern Japan, 

 which we have compared with specimens from Alaska and Puget 

 Sound, and have found them to l)e similar. 



Specimens from I])i and Mino rivers near Ogaki in Mino seem to be 

 inseparalde from the naked specimens from Colton, California (called 

 " Gasterosteus wilUamsoni''-). They ditfer greatly from the marine 

 form in being deeper, in having the ventral plate broad and short, in 

 being only partially armed, in being conspicuously mottled, and in 

 exhibiting all of the differences which fresh-water specimens at the 

 extreme of variation from California and Alaska exhibit. Since it has 

 not been possible to satisfactorily separate the Western American 

 fresh- water species from those found in the sea, we can not consider 

 these as distinct even though we have no intergrading forms at hand. 



Formula? of soft rays of dorsal and anal: 



(Kata^paKroz^ catwphr actus ^ mailed.) 



