TIIK IIATKACIIIA OF NoKTII AMKliKIA. 



;'»o;; 



cranial iiitc;;iiaieiit. Tho speck's Ik'Ioiij;' to the wi'stcni anil sontli- 

 westciii parts of the iicarctic realm. Tliey arc distingnislied as follows: 



a. Tympiiiiic (UnU diHtinct; no ^IiukI on tibia. 



Intororbitiil width inirrow, ont(uin;; li'n<;lli of tiltia foui' tinum; vonicrinii 

 tcolh between choanii- ; color j;<'nei'iilly daik, witb or witliout [lalo Htripcs. 



•S. hammoiidii. 

 (XiX. Tynipiinic disk concoalfd ; a larj;"' j^landoii tho ii|>im'I' nidi^ of (be tibia. 



Intei'orbital widlli narrow, entcrin;; tiliia tbicc tinicH; vonirriiK^ tet^tli a lilllc 

 ])osterior to narcs; colorM piilo .S'. miilliplhald. 



Sl'EA IIAMMONDII Haird. 

 (.'oiM', Journ. Ac. I'liila. Ci), vi, ISCC, p. hi. 



Svupliioinin hainminidii Haird, Ut-pt. Kxpl. Surv., iv, Ivt'iitil., IM.V.), IM. '^f*, lij;. •_'; Copf, 



I'rocood. Ac. I'liiia., l"<(r.t, p. .Ml; IJonlenjjcr, Cat. Hatr. Sal. ISrit. Mm., lHH-2, p. t:{.'i. 

 ScdjiliiitpuH liomhi/roita Copi', I'nicccd, Ac. I'bila., iHtiH, p. .^;i; Koiilcn^cr, Cat. Hatr. 



Sal. IJrit. .Mas., ls«-,>, p. >;!.-,. 

 Simibomhi/rotin Cojie, .lourn. Ar. i'liila. C-i) vi, iHtilJ, p. 81. 

 Sped Hlaiinalix Coiic, l'. S. (1. (1. Siirv. \V. of ItKttli Mcrid., v, Zool., p. .V,',"), IM. •^."•, 



li-,'.s. (i-H. 

 S(\nilii>jiHn aliKjnaliH ltoul(Mi;r<!r, Cat. Hatr., Sal. lirit. Mas., IS&2, p. VM't. 

 ^^laiihioiiun tliiijiHii KriK'clii, Hull. Soc. I'liiloni. (7), ill, lH7i», p. '2U, and Miss. Sci. 



.Mcx., ISatr., p. HI, I'l. ".>, li.;. t ; Hoiilcii>,'cr, Cat. Hatr. Sal. Hrit. Mns., 18-X', p. J;'.!). 



This is a widely distributed and variable s[)ecies, presenting sncli 

 diversity in some res|)ects as to be interesting as an example of the 

 appearance of important (tharacters in the conrse of descent. It is in- 

 teresting also from its habits, adapted as they are to the exigencies ol 

 a dry climate, in which the o[)pi)rtnnity for aquatic life is i)recarions, 

 and the metamorphosis corresi)ondingly liable to inodilication. 



I include three subspecies under thecommo:i head, which are delined 

 as follows : , 



(»i'M"rally no frontopar' '-il fontanclli' ; head piano above; a liuij^itudinal pale ban.l 

 on eaeli side of IkI' .; larj^er; skin tnbercnlar S. Ii. iiitennuittaiin. 



.\ frontoparietal fontanelle; head plane or convex above ; no lonj^itudinal li;.v'it 

 bainls ; .skin smoother ; snia]|<>r *'. /i. hdmmoiiilil. 



A frontoparietal fontanelle; head very convex at tlie, interurbital rej^ion ; skin nearl,' 

 smooth ; color.s palo ; si/.c least S. It. hoiitbij'roiis. 



I had first placed the S. h. hitcnnontana in the genus Scaphiopus, 

 while the two other subspecies were placed with the S. utHltipUcafa 

 in a distinct genus, Spea, which was characterized by the presence of 

 a frontoparietal fontanelle. This character is generally constant, al- 

 though its inconstancy as a s;>eci(lc character is t> be expected some 

 where. The genus Spea is the seat of the failure of this generic char 

 acter to coincide with the other detinitions of a species. In one of the 

 four specimens of the subspecies Intermontanus 1 find the fontanelle 

 present, while in three it is absent. In a fifth specimen it is rei)re- 

 sented by a fissure between the frontoparietal bones. 



The S. h. bombifronn appears to be, at first examination, a well de- 

 lined species, The interorbital protuberance is a striking character. 



i-Hj 



!P I 



