Mollusca of the Arabian Sea, d:c. 91 



A species apparently common^ though local, in the Persian 

 Gulf, and probably extending in both a southerly and east- 

 ward direction. It has hitherto been confounded with 

 M. poci/ica, Reeve, of which I possess an original type from 

 the collection of the late Sir D. Barclay, Bart., the example 

 figured in Sowb. Thes. Conch, t. ccclxxviii. fig. 630, which 

 exhibits a form more compressed^ strongly shouldered, and 

 angulate in the upper portion of each whorl, very rugose, and 

 ribs fewer but more m.arked in proportion. I consider this 

 latter species nearer to the variable J/, cadaverosa, Reeve, so 

 abundant in the Philippines, and especially the islands of the 

 Pacific. BJ. Wisemanni, Dohrn, is in size nearer our shell, 

 but the clearly defined and frequent longitudinal ribs, un- 

 varying in all the specimens I have seen, amply distinguish 

 it. I am much indebted to Mr. Sowerby for especially calling 

 my attention to this hitherto neglected species. 



Erato olivaria, sp. n. (PI. I. fig. 9.) 



E. testa arcuato-pyramidata, solida, Icete olivacea, apice subconico ; 

 anfractibus quatuor, supernis interdum rugosulis, interdum 

 laevibus, ultimo anfractu Isevi, rapide accrescente, tumidulo, 

 pj'riformi, apud basim paullum attenuate ; apertura angusta, 

 oblonga ; labro exteriore crassiusculo, denticulis quindecim intus 

 praedito, margine columellari, et prgecipue versus basim, incras- 

 sato, denticulato. 



Long. 6, lat. 3"25 mm. 



Hal). Karachi. 



A few examples of a somewhat solid smoothish Erato, 

 conspicuous for its bright olive hue ; the apex is subconical ; 

 whorls four, the last being large, pyriform, somewhat attenuate 

 at the base, the mouth narrowly oblong; outer lip thickened, 

 denticulate within, with fifteen little teeth ; columellar margin 

 thickened, especially towards the base, and then also den- 

 ticled. This species slightly resembles the European E. Icevis, 

 Donovan. 



The only other known smooth species of a uniform green 

 or olive hue is E. 'praycnsis, Rochbrune, from the Cape Verd 

 Islands, but, from description^ would seem to differ both in 

 form and lip-characters. 



Natica Ponsonbyi, sp. n. (PI. II. fig. 4.) 



K. testa globosa, anguste sed profunde umbilicata, solida, laevi, 

 paullum nitida, albida ; anfractibus 4-5, apicali fere immerso, 

 nigro, caeteris supra suturas castaueo-fasciatis, ultimo anfractu 



