DA COSTA : ON THE GENtTS KHODEA, 



30-5 



only were found by Mr. Rosenberg during bis recent travels in 

 Ecuador, one being dextral, tbe otber sinistral. 



5. Ehodea CEossEAisrA, n.sp. Eig. Y. 



Testa cylindracea, apicem versus sensim angustata, tenuis, sub- 

 pellucida, cornea ; anfractus 1 3, superiores 3-4 Igeves, convexi, 

 sequentes 2-3 convexi, cseteri fere plani, oblique tenuiter et confertim 

 striati, sutura obliqua inter anfract. paucos ultimos carinata, sejuncti, 

 ultimus ad peripheriam acute carinatus, infra carinam profunde 

 excavatus ; apertura irregulariter quadrata, bicanaliculata ; columella 

 spii'aliter torta, intus ascendens, umbilicum fere ad apicem, pervium 

 formans ; labrum tenue, in medio angulatuni, canaliculatum, infra 

 concavum. Long. 31, diam. 5 mm. 



II. III. 



Fig. I. Portion of Rhodea gigantea, Mouss., with the outer walls removed to 

 show the spiral columellar fold. 

 ,, II. A young specimen of the same, showing the form and the columeUar fold. 

 ,, III. Rhodea tequatoria, n.sp. Dextral form. 



,, IV. . Sinistral form. 



,, V. ■ Crosseana, n.sp. 



Hob. — Eiver Dagua, United States of Colombia ("W. E. H. 

 Rosenberg). 



Type in the British Museum (Natural History). 



Yery much larger than R. Pfeijferi, Crosse, with differently 

 proportioned whorls ; the body -whorl more deeply excavated beneath, 



