72 



Triton lineatus. Trit. testd turritd, crassd, pallescente ,fuJvo 

 variegatd ; anfractihus novem, obsolete trmisversim sulcatis, suleis 

 hrunneia, iitterstitiis granulosis ; varicibus obtusis ; aperUird ob- 

 longd, labio externo intus sulcato ; labio intenio aiitice ręfleso, 

 incrassato ; columelld rugulosd: long. 2'6, lat. V poli. 

 Hab. 



Much larger than any of the others. These seven may be re- 

 garded by some as mere varieties of Trit. maculosiis of Lamarck, 

 although I am fully satisfied of their being perfectly distinct spe- 

 cies. 1 am, Iiovvever, of opinion that it matters not whether they be 

 regarded as species or varieties, seeing that it is equally neces- 

 sary to describe them all particularly. — G. B. S. 



Triton decollatus. Trit. testd oblongo-subturriid, pallescente^ 

 Jusco variegatd ; apice retuso ; anfractibus guinąue, primis duo- 

 bus reticidatis, religuis ventricosis, transversim sulcatis, suleis 

 brunneis, ititerstitiis planinsculis ; sulurit distinctis ; varice unico; 

 aperturd ovatd, peritremale crenato ; labio interno antice re- 

 flexo, incrassato : long. !•, lat. O'^poll. 

 Hab. ad Insulam Annaa. 



Found on the reefs, and easily distinguished from all the above 

 by the fact of its being decoilated and by its having only a single 

 vari.v. — G. B. S. 



Genus Bulinus. 

 BuLiNUS DISCREPANS. Bul. testd oblongd, sabacuminatd, albi- 

 canie, nitidiusculd ; anfractibus ąuinoue vel sex gibbosiusculis, 

 lineisjuscis, obliguis irregidnriter pictis, transversis duabus infe- 

 rioribus subdistantibus ; aperturd subovatd,superne subacuminatd: 

 long. O-l, lat. 0-33 poli. 

 Hab. sub cortice arborum in Americi Centrali. 

 This was found at Conchagua ; it is somevvhat similar to Bul. 

 nitidus, but upon comparison may easily be distinguished. — G. B. S, 

 Bulinus calvus. Bul. testd oblongd, subturritd, pallescenti- 

 brunned ; an/ractibus septem breviusculis, rotundatiusculis ; aper- 

 turd ellipticd, mhrgine intemd incrassato, ; umbilico mediocri : 

 long. 0-6, lat. 0-25 poli. 

 Variat nonnunquam linea spirali albicante. 

 Hab. ad Insulas Gallapagos. 



Found on dried tufts of grass on James's, one of the Gallapagos 

 Islands.— G. B. S. 



Bulinus ustulatus. Bul. testd oblongd, subacuminatd, Jusco- 

 nigricante; aiifractibus sex vel septem gibbosiuscidis , lineis non- 

 nullis paUescentibus pictis ; aperturd ellipticd, columelld cras- 

 siusculd, albicante, margine acutd : long. 0"6, lat. 0'3 poU. 

 V^ariat nonnunquam linea spirali pallida. 

 Hab. ad Insulas Gallapagos. 



Found under detached pieces of lava on Charles's, one of the 

 Gallapagos Islands. — G. B. S. 



Bulinus pallidior. — Bid. testd oblongd, subacuminatd, totd al- 

 bicante ; atifractibus sex, gibbosiusculis, ultimo maximo, inferiori- 

 bus postice marginatis ; aperturd oblongd, intus pallide brunned. 



