Jordan arid Evertnann. — Fishes of North America. 681 



Intestinal canal as long as body. Dorsal small, far back; distance from 

 its insertion to candal half that to snout, its first ray about over middle 

 of anal ; anal laiger and higher than dorsal. Light olive, each scale 

 edged witli darker; a very narrow dark streak along sides; top of head 

 dusky; a more or less distinct triangular bluish-black bar below eye; 

 sides and belly anteriorly dusky with dark dots; a black blotch on each 

 side of belly, caused by the black internal organs showing through the 

 skin ; young specimens often uniform yellowish ; fins dusky ; the caudal 

 usually with cross series of tlots. Length \\ to 2 inches. Males very 

 scarce,* and very small, about \ to 1 inch long, the anal process as long 

 as head. The ordinary form, to which the w^xwq iiairuvVxs has been given, 

 has usually 8 dorsal rays, a dark suborbital bar, and the fins more or less 

 speckled. Some specimens from Texas have fewer spots, the body and 

 fins nearly plain, and the dorsal rays G or 7. These differences are proba- 

 bly of little value. If, however, the distinction holds good, the common 

 form (Delaware to Texas) should stand as subspecies 2)airueli^, the name 

 affiuis having priority ; the names Iwlh-GoU, melanops, and atrilatits being 

 synonyms of _/j((/r(/e?(s. Marshes and lagoons of the South Atlantic and 

 Gulf coasts, Delaware to Mexico, and north to southern Illinois, in brack- 

 ish or fresh water; excessively common southward, usually in clear 

 water, but in sluggish rather than running streams. The young are pro- 

 duced in summer, when about i of an inch long.t (afjinis, related, to G. 

 holbrooki.) 



IMemniMa f#Hi.«,t Baiiid & Girard, Proc. Ac. Nat. 8i-i. I'liila., lHr>:',, I'.lKl, Rio Medina and 



Rio Salado, Texas. (Coll. Clark.) 

 Ileteramh-ifipatrueJls, Baird & Girard, Proc. Ac. Nat. Sci. Pliila., 1S,M5, :'.!«), Rio Sabinal, Rio 



Nueces, and Elm Creek, Texas. (Coll. Clark.) 

 Heleranilria holhrooki, Agassiz, MS., ]S.'>4, Charleston, South Carolina, 

 Gamhnsia holhrooki, Girard, Proc. Ac. Nat. Sci. Phila., \%b'.\ (U, Palatka, Florida; Gi-xther, 



Cat., VI, 334, 18GG. 

 GamhuMa speciosa, Girard, Proc. Ac. Nat. Sci. Phila., 1859, 121, Rio San Diego, New Leon, 



Mexico ; said to liavo fin rays in small uumlier; not counted iu description. 



*0f 69 examples from the lower Potomac examined by Dr. Hugh M. Smith, G8 were females. 

 The stomach of cue specimen contained alga;, diatoms, and fragments of a mosquito. 



t " Mr. A. A. Duly has informed me that he has witnessed the act of copulation and the birth 

 of the young of Gamhusia. lu coitus tlic male's head is turned in the direction of the tail of the 

 female, the prolonged anal tin seeming to be thrust iuto the external oiieniug of the ovarian 

 duct or genital pore of the female, which lies just in advance of the anal tin. The young, when 

 born, are stated by Mr. Duly to be about % of an inch iu length, and to bo expelled in a single 

 mass, consisting of 8 to 11 young fi.-^hes at a single effort. This nias.s, as soon as it escapes, is 

 Been to be composed of the infant Gaitibmias, which at once separate and swim away. No mem- 

 branes seemed to be expelled togeihcr with tlie mass of young, so that it is probable that iu this 

 species, as in Anablejjs and the Euilncloci'lu; the fietuses rupture the follicles in which they were 

 developed a short time before birth. I say a short time before birth, because our observations 

 indicate that, unliUe yln((h/e;)s and Mkrometriis, the development of Giwihiisia is es.sentially com- 

 pleted within the follicles, and no yelk sac remains outwardly visible when the young are set 

 free. My iuformant also tells nie that the parent fishes devoured their young as soon as they 

 were born if they were not separated, by tiiiiisferring one or the other at once to another 

 acpiarium. Fright seemed to hasten or jjrecipitato the jiarturition, which Mr. Dulv tells me 

 actually took place under such circumstances. lie also noticed that more than one brood 

 seemed to be produced by the same parent consecutively and duriug the same season, and ho 

 has reason to think that more may have been jiroduced, as his observations only extended over 

 the latter part of summer with adults brouglit from Cherrystone, in August "and September, 

 which ho kept in aquaria in the National Jhiseum." (Ryder, Proc. U. S. Nat. Mus., 1885, 

 1.55.) ^ ' ' 



X GamhixUi affiuis (Baird & Girard): Body modonitely stout. Dorsal and anal fins similar in 

 size and shajie, the latter not much advanced. Coloration plain; dorsal and caudal dotted with 

 black. Head 4; depth 3|. D. G; A. H.— Girard. 



