EASTERN PROVINCE SOUTHERN REGION SPECIES. r)55 



incrustata without tlie splitting of the inner cutting point, but it is 

 otherwise in rortex and turb'miformis. Tlie marginals are low, wide* 

 the inner cutting point is long, blunt, simple in Inr/crsolli and incrm- 

 tata, bitid in the other species. The outer cutting points of all are 

 short, varying in number from one to three. For those of Lansingi see 

 below. 



Thus in this genus, as in most of the others, we find a certain range 

 of variation in the dentition and jaw. 



Mict'opliysa incrustata, Poey. 



Shell umbilicated, depressed, smooth, horn-colored, usually iucrusted 

 with dirt, with crowded strife ; spire slightly elevated, com- fig. 383. 

 posed of 4 or 5 well-rounded whorls, separated by a deeply |^^?K 

 impressed suture ; beneath with a broad umbilicus, one- 

 third the diameter of the shell, exhibiting all the whorls 

 within ; aperture circular, being but slightly inii)inged upon ; | 

 by the penult whorl, its extremities joined by a slightly ap- 

 pressed scale of enamel, rendering the peristome continuous; M.incrmtata. 

 peristome slightly retiexed, so as to render the aperture somewhat 

 campanulate. Greater diameter 4§, lesser 4"™; height, S""". 



Helix incrustata, Poey, Meiuorias, i, 208, 212, pi. xii, figs. 11-16. — Pfeiffer, Mod. 



Hel. Viv.,iii, 632.— W. G. Binxey, Terr. Moll., iv, 68; L. & Fr.-W. Sh., i,70, 



fig. 117 (1869). 

 Helix saxicoJa, Gotld, in Terr. Moll., ii, 174, pi. xxis, a, fig. 4, not Pfeiffer. 

 Helix incrassctta, Reeve, Con. Icon., 972. 



Pseudohyalina incrustata, Tryon, Am. .Jonrn. Conch., ii, 265 (1866). 

 Microphysa incrustata, W. G. Binkey, Terr. Moll., v, 170. 



Galveston and Corjius Christi, Tex. ; also near Havana, Cuba. It 

 must be considered a species of the Southern Eegiou. 



Its circular, camjianulate aperture, almost disconnected with the 

 preceding whorl, is one of its most striking peculiarities. 



Jaw low, wide, slightly arcuate; ends blunt, but little attenuated; 

 anterior surface with numerous crowded ribs, bluntly denticulating 

 the lower margin. 



Lingual membrane with 13-1-13 teeth, of which 5 are perfect later- 

 als. Centrals quadrate, tricuspid ; laterals like centrals, but bicuspid; 

 marginals low, wide, with one inner long, blunt, and several short, 

 side, blunt cutting points. (Terr. Moll., Y, Plate III, Fig. S.) 



I formerly placed this species in Patula, but having recently ex- 

 amined the jaw of a dried specimen in my cabinet (collected over thirty 

 years ago at Galveston), I am led to believe that Von Martens is right 

 in placing it in Microphysa. 



