MARINE INVERTEBRATA OF GRAND MANAN. 21 



L. TENUISULCATA, St. Coiiinion Oil mudcl}' bottoms. 



Mytilus decussatus, Mont. Found at low-water mark, attached to the under 

 side of stones by a byssus. Also in 40 f. gravel. 



M. CORRUGATUS, St. 35 f. gravel, on the Hake Ground. 



M. DiscoRS, Lin. Found in nests formed of various marine substances, under 

 stones at low water, and to a depth of 40 f. 



M. LEviGATiTS, St. Dead in 35 f. gravel. 



M. DiscREi'ANS, Mont. Coinmon at various depths; sometimes growing very 

 large — one occurred li in. in length. 



M. MODIOLUS, L. This species here inhabits the shores, being seldom found in 

 deep water. 



M. EDULis, L. Ver}^ abundant at low-water mark, but usually small. 



Thyasira GouLDii, St. In 4 f. sand, ofl' Duck Island weir; large specimens in 

 25 f. mud. 



Cardita borealis, Con. Duck Island, at low water under stones, attached by 

 a minute byssus. In deep water it is large and very common. 



AsTARTE SULCATA, Flem. Common in deep water on muddy bottoms. 



A. QUADRANS, Gould. Occurs very rarely here. 



Cyi'RINA Islandica, Lam. Earely found. 



Cardium Islandicum, Linn. Full-grown specimens, dead, are common on nulli- 

 pore bottoms, in 3 to 6 f.; the young, alive, are dredged in 20 to 40 f. mud. 



C. pinnulatum. Con. In 4 f , coarse sand. 



Mactra ponderosa, Phil. Common in sand at low water, buried at a depth of 4 

 inches. 



M. soLiDissiMA, Chemn. Found sparingly accompanying M. ponderosa. 



Tellina fusca, Phil. Inhabits the higher levels of the littoral zone. 



T. PROXiMA, Brown. Among nuUipores on sandy ground, at low water, and in 4 f. 



SoLEN ENSis, L. At low water, in sand; rare. 



Thracia truncata, Migh. In 10 f coarse sand, off Cheney's Head. 



T. MYOPSis, Beck, in MoUer's Index MoUuscorum Groenlandia?. Comparison with 

 si)ecimens of this species from Greenland has convinced me of its identity with my 

 T. Couihoinji. I was misled by the inaccuracy of MoUer's description, especialh" in 

 giving "ossiculum nullum." I have observed the ossiculum in several specimens. 



T. CoNRADi, Couth. Rare. 



Lyonsia iiyaijna. Con. In 10 f. sand, off Cheney's Head. 



Pandora trilineata, Say. In 5 f. mud. 



Ne.era pellucida, St., n. s.. Fig. 13. Shell small, thin, pale white, subovate, 

 ventricose anteriorly, and contracted posteriorly into a short but distinct rostrum. 

 Beaks small, tumid, and placed a little before the middle. Surface nearly smooth 

 about the beaks, with irregular, distant striffi of growth near the margin, which 

 become sharp and well-marked on the rostrum. Within, smooth and glossy; 

 teeth very minute. Epidermis white, sometimes pale greenish on the beaks, and 

 brownish on the rostrum. Length, .19 inch; height, .12 inch; width, .11 inch. 



It is the first of this genus taken on our coast, and resembles the young of iV. 

 4 



