M Y T I L U S 



Species 30. (l\Ins. Ciiming.) 



Mytilus obscurus. Myt. testa mbquadrato-ohlongd, 

 convexd, posttce hand impressd, concentrice striata; 

 albida, sordide olioaceo aut rvfescente tinctd. 



The obscure Mytilus. Shell somewhat squarely ob- 

 oblong, convex, not impressed on the posterior side, 

 concentrically striated ; whitish, tinged with dull- 

 olive or green. 



DuNKEK, Pro. Zool. Soc. 1856, p. 360. 



Halj. Sydney. 



Distinguished liy an even convex growth, not impressed, 

 as is commonly the case in this genus, on the posterior 

 side. 



Species 31. (Mus. Cuming.) 



Mytilus obesus. Myt. testa elongato-ovatd, soliduld, 

 versus umhoms sitbangulato-attenaatd, rosiratd, lavi- 

 gatd, plus minus rude erosd, obscure divaricatim pli- 

 catd ; intense purpureo-atrd. 



The stout Mytilus. Shell elongately ovate, rather 

 solid, somewhat angularly attenuated towards the 

 umboes, beaked, smooth, more or less roughly eroded, 

 obscurely divaricately plicated ; deep purple-black. 



DuNKER, MS. Mus. Cuming. 



Hub. Van Diemen's Land ; R. C. Gunn. 



A shell of solid structure and rough purple-black sur- 

 face ob.?curely divaricately waved with rude folds. 



Species 32. (Mus. Cuming.) 



Mytilus gracilis. Myt. testa anguste elongald, tenia, 

 versus umbunes attenuate productd, postice vix im- 

 pressd, concentrice dense stria td ; albida, epidermide 

 corned olivaced et intense caruko-viridi indutd. 



The slender Mytilus. Shell narrowly elongated, thin, 

 attenuately produced towards the umboes, posteriorly 

 but little impressed, concentrically densely striated ; 

 whitish, covered with an olive and dark blue-green 

 epidermis. 



Hab. Mexico. 



Distinguished in a conspicuous degree by its narrowly 

 elongated form. 



Species 33. (Fig. a, b, Mus. Cuming.) 

 Mytilus edulis. Myt. testa obligue trigond, concentrice 



striatd, carulescente-nigrd, vel olivaced nigro-radiatd, 



postice. subcompressd, antice arcuatim impressd. 

 The edible Mytilus. Shell obliquely triangular, con- 

 centrically striated, blue-black or olive, rayed with 



black, rather compressed posteriorly, anteriorly arcu- 



atcly impressed. 

 LiNN.«us, Syst. Nat. (13th edit.) p. 1157. 

 Mytilus pellucidus, Pennant. 



Mytilus incurvatus, Pennant. 



Mytilus vulgaris. Da Costa. 



Mytilus Jlavus, Poll. 



Mytilus sagittatns, Poli. 



Mytilus abbreviatus, Lamarck. 



Mytilus retusus, Lamarck. 



Mytilus hesperianus, Lamarck. 



Mytilus dilatatus. Gray. 



Mytilus subsaxatilis, Williamson. 

 Hab. North Atlantic shores. 



The numerous synonyms annexed to this well-known 

 species, evidence in a striking degree the many variations 

 it assumes under ditferent circumstances of habitation. 



Fig. 34. (Mus. Cuming.) 



This tine shell proves to be a dark full-grown variety of 

 M. Ifitifs, represented at Plate IV. 



Species 35. (Mus. Cuming.) 



Mytilds pilosus. Myt. iestd late trigond, versus urn- 

 bones valde (jibbosd, postice concavo-impressd, midique 

 forliter liratd, liris granulalo-scrralis ; liiteo-olivared, 

 sparsim pilosd. 



The hairy Mytilus. Shell broadly triangular, very 

 gibbous towards the umboes, posterioriy concavely 

 impressed, everywhere strongly ridged, ridges granu- 

 larly serrated, yellowish-olive. s])aringly hairy. 



Recluz, MS. in Mus. Cuming. 



Hub. ? 



A broadly triangular shell, very gibbous and contracted 



towards the umboes, the surface being densely seirately 



ridged throughout, covered with a yellowish-olive horny 



epidermis, bearded with rather distant bristly hairs. 



January, 1858. 



