1«1 



5. Mactra (Mactrella) lacinata, n. s. M. testą parva, te- 



nuissima, cmerea, ventricosa ; postice angulata, carina modica, \> • ^'^ ' - 

 fimhnata ; lamori, concentrice vix undulata, rugvHs epider- — /m. ^ 

 midis tenms suhdistnntibus ornata ; subceąuilaterali, umbonibus ' *- 1 \ 



prominmtibus ; dent. card. parvis, lat. acutis, haud diatanti- 

 bus; sinu pallii parvo, subangulato. 



Long. •:,%, lat. -69, alt. -4 poli. 



Hab. In Sinu Panamensi; legit T. Bridges. Mus. Cuming, sp. 



Has a general similarity to M. angulata and kindred species. Re- 

 markable for the epidermal fringe ou the keel and regular concentric 

 wnnkles. 



6. Cyclina prodtjcta, n. s. C. testą tenui, ventricosiore, alba, O. V'^ 

 ventraiiter producta ; concentrice tenuissime striata ; margini- 

 bus subregulariter arcuatis ; umbonibus eleganter ineurvatis ; '%-\C'^ " '"' 

 lunula nulla, linea cordiformi vix monstrante ; area ligamenti 

 elongata; dent. card. valva altera postico bifido, anticis ii., 

 contigttis; altera posticis ii. acutis, elongatis, antico acuto] 

 sinu pallii subangulato, umbones versus fere dimidium ascen- 

 dente. 

 Long. 1-62, lat. 1-58, alt. 1-05 poli. 



Hab. In Sinu Panamensi; legit T. Bridges. Sp, un. in Mus. 

 Cuming. 



In shape somethiug likę Cgrena maritima, C. B. Ad., but in 

 habit resembliug Cyclina subąuadrata, Hanl. (=Artemis saccata 

 Gould). * 



7. Melampus Bridgesii, n. s. M. testą parva, ovali, nigro- 

 fusca, nitida; anfr. viii., sutura haud impressa, in spiram 

 tenue spiraliter striulata ; marginibus spiree regulariter excur- 

 vatis; apertura pyriformi, labro acuto, nec calloso nec dentato; 

 columella triplicata ; plicis, antica spirali, obliąua ; media 

 ttcuta, transversa, subparietali ; postica parietali, parva. 

 Long. -28, long. spir. -08, lat. -12 poli., div. utraoue parte vari- 

 ante. 



Hab. Ad ora Sinus Panaraensis; legit T. Bridges. Sp. tria in 

 Mus. Cuming. 



Has the general appearance of M. Adamsianus, Pfr., from N. 

 Ireland, but is much more slender, with a simple labrum. 



8. Umbrella ovalis, n. s. U. testą " U. Indicse" simili ; sed 

 margine haud undulato, regulariter ovali; apice spirali, sub- 

 prominente, minus inceąuilaterali ; epidermide tenui, haud 

 nitente ; adulta intus aurantia. 

 Tęst. jun. long. 1-93, lat. 1-58 poli. 



Hab. Ad ostia fluminis Chiriqui, in Sinu Panamensi; legit T 

 Bridges. Sp. duo in Mus, Cuming. 



Conceming this remarkable shell, hitherto only fouud in the old 

 world, and, in spite of the bulk of its animal, not observed bv either 

 ^M ^'i^l?,^' ^™^" ^^«"^S' «•■ ^'r. Hinds, Mr. Cuming writes that 

 No. CCCXI.— Proceedings of the Zoological Society. 



