192 [October, 



the same form ; the last segment or active polyp is campanulate and is supplied 

 with cylindrical, ciliated arms arranged in a circle around the mouth. 



Urnatella gracilis, Leidy. 



Stems single, or in groups up to six in number, attached at the lower ex- 

 tremity by means of a sienna colored granular substance. Urniform segments 

 .225 m.m. long by .18 m.m. broad, becoming smaller towards the free end of 

 the stems ; body portion of each urniform segment translucent whitish, with 

 sienna colored transverse striae and punetae, and having on each side near the 

 bottom a rounded process, the remains of former branches ; the narrow top and 

 bottom portion of the segments brown in color and annulated. The antepenul- 

 timate and penultimate segments and their branches oblong, translucent. Polyp 

 .225 to .45 m.m. long, campanulate ; expanded mouth circular, the diameter 

 equal to the length of the body, surrounded by fourteen cylindrical, ciliated, re- 

 tractile arms. Stems up to 4 m.m. in length. 



Habitation. On the underside of stones in the river Schuylkill below low 

 water, in Philadelphia city. 



Plumatella vesicularis, Leidy. 



Ccencecium radiating and branching, attached, colorless and transparent; each 

 segment slightly dilated and much broader than the protuberant orifices of exit. 

 Length of the segments about 1. m.m., breadth 1 m.m. Animal colorless. Ova 

 oval lenticular, (with an annulus but without spines.) 



Habitation. Found in the Schuylkill river with the preceding, on the under 

 side of flat stones. 



Remarks. This species of Plumatella is as limpid as the water in which it 

 lives ; and it resembles rows of colorless vesicles with a whitish line passing 

 through their axis. Frequently it is observed with rows of imbricated blackish 

 eggs instead of the latter line. Patches are found from a quarter of an inch to 

 two inches square. 



Notices of new Reptiles from Texas. 

 By Edward Hallowell, M.D. 



Family LACERTID^. 



Genus Cnemidophorus, Dum. et Bib. 



Ciiemidophorus guttatus, nob. 



Char. Head olive color ; body greenish olive, with eight lines of the same 

 color; intermediate spaces upon sides brown; sides presenting numerous white 

 spots arranged in longitudinal rows ; under surface dark blue, marked with 

 white ; of anterior extremities deep blue ; of posterior extremities and of tail 

 white; scales of the body very small; subgular fold margined with a row of 

 large smooth scales ; several smaller rows anterior to them ; eight rows of 

 scales upon the abdomen ; 16 femoral pores on each side very distinct. 



Dimensions. Length of head 1 inch ; greatest breadth f in. ; length of head 

 and body to vent 3$ inches ; of tail 4f inches ; of anterior extremities 1 l-8th in.; 

 of posterior 21 in. 



Habitat. Texas. , 



Gen. Obs. Readily distinguished from Ameiva sexlineata ; allied to Cnem. 

 gularis, but the latter is without spots. 



Family CROTALID^. 



Genus Crotaltjs, Linn- 



Crotalus ornatus, nob. 



Char. Three large plates in front of upper part of head on each side ; nasals 

 large ; posterior part of head covered with smooth scales ; rostral rather large ; 

 eighteen supralabials, the 6th, 7th and 8th the largest ; a small plate between 

 the rostral and first supralabial and anterior frontal ; 27 rows of scales ; ground 



