M Y T I L U S. 
496 
that the eggs were fir ft: formed in the fleftiy part of the 
mufcle; but, as they advanced in growth, they were moved 
to that part which is called the Liard; and which, by the 
great number of the young mufcles contained therein, 
then fwells in bulk. 
“ Some of thefe mufcles I opened in the prefence of 
the Engraver, in order that, as foon as I had taken fome 
of the young ones out of their receptacle, he might make 
a drawing of them, for, were they buffered to Hand but a 
few' hours, their true figure would be loft:. The unborn 
mufcles being put into a glafs tube, and placed before the 
microfcope, I law with aflonifhment a moll pleaiing fpec- 
tacle; for every one of them, each in its particular mem¬ 
brane or covering, had a flow circumvolution, and that 
not for a fliort fpace of time, but fuch turning round or 
rotatory motion was obfervable for three hours after¬ 
wards ; and it was the more curious, becaufe the young 
mufcles, during the whole of their motion, conftantly kept 
in the centre of their membranes, juft as if one were to 
fee a fphere or globe revolving upon its axis. This un¬ 
commonly pleafing fpedlacle was enjoyed by myfelf, my 
daughter, and the engraver, for three w'hole hours, and 
we thought it one of the moft delightful that could be 
exhibited.” We are lorry we cannot make room on our 
plate for the accurate reprefentation of this fpecies which 
Mr. Hoole has furnifhed. One peculiarity, how'ever, we 
mud not omit to notice; namely, that, inftead of one 
ftrong tendon, or finew, for the purpofe of opening and 
Ihutting its Ihell, as in the fait-water mufcle and the oyf- 
ter ; this frelh-water mufcle, on account of the length of 
its Ihell, has two, which are fixed near the extremity of 
the lliell at each end, whereas, in thofe that poftefs but 
one of thefe organs, its lies in the moft favourable pofi- 
tion, near the middle. Hnole's Leeuwenhoek, Part I. 
21. Mytilis viridis : Ihell fmooth, ovate, membranace¬ 
ous, and pellucid, with a terminal hinge. It inhabits the 
Southern Ocean ; the lliell is green, very thin, and about 
the fize of a man’s nail. 
22. Mytilus ruber: lliell wrinkled, the valves oblique 
and dilated in front; margin of the hinge equalling the 
tip. It inhabits the Southern Ocean. The fhell is red 
and convex, but very minute, with a Ihort comprefled 
tooth in the hinge. 
23. Mytilus albus : Ihell tranfverfely ftriate; beaks 
gibbous; hinge lateral. It inhabits the fhores of Chili. 
The lliell is about fix inches long and three and a half broad, 
covered with a blue Ikin, under which it is fnowy, with 
a blue tinge; the fifh is white, and very excellent food. 
24. Mytilus ater: Ihell grooved and fcaly behind. It 
inhabits Chili; lliell rough ; lefs than the laft ; dull-blue : 
the fifti is black, and not eatable. 
25. Mytilus difcors : Ihell oval, horny, fub-diaphanous; 
the extremities are ftriate longitudinally, the middle tranf¬ 
verfely. This fpecies is found in the European and 
Southern oceans, affixed to rocks and other fliells by its 
beard; the Ihell is final 1, brittle, and femi-tranfparent; 
the fifti is not eatable. 
26. Mytilus hirundo: Ihell fmooth ; valves two-lobed. 
It inhabits the Indian, American, Mediterranean, and 
Atlantic, feas, in great varieties of fize, thicknefs, form, 
colour, and markings ; the (hell is contracted at the bafe, 
with very fine and crowded tranfverfe wrinkles; within 
pearly. See Conchology, Plate XVI. fig. 2. 
27. Mytilus pholadis: lliell oblong, more obtufe on 
the fore-part, rough,With tranfverfe wrinkles. It inha¬ 
bits the North Seas, and penetrates beds of coral arid 
rocks, like the Pholas, which fee. It is about one inch 
and a half long, and one and a quarter broad ; the ends 
are not quite clofed ; the hinge is without teeth, or with 
a very fmall one. See the article Helminthology, 
vol. ix. p. 355. 
28. Mytilus ftriatulus : fhell very finely ftriate ; hinge 
terminal, one-toothed. It inhabits the Northern and 
Indian Seas; is one inch and a quarter long, and one and 
a half broad. 
29. Mytilus vulgaris: lliell flattifli on one fide, and in- 
flefted, with convergent incurved beaks ; the hinge is 
one-toothed. In inhabits the American Ocean. 
30. Mytilus plicatus : lliell rhombic, tranfverfely ftriate 
and wrinkled ; beaks incurved. Inhabits the Nieobar- 
iflands. 
31. Mytilus niveus : fhell ovate, fubdiaphanous, with 
very fine longitudinal ftriae ; margin acute ; hinge two¬ 
toothed. Inhabits the Nicobar-iflands; but is very rare. 
32. Mytilus afer: fhell nearly triangular, dilated be¬ 
fore and flattifli, gaping behind; beaks pointed, turned 
back; margin very aCute. Inhabits the fouthern parts 
of the Mediterranean, and the fhores of Africa. It is 
four inches long and two broad; within ochraceous with 
iridefcent colours, without ftraw-colour,mixed with green- 
iffi and yellowifh, and marked with reddifh lines arid an¬ 
gles. Perhaps a variety of Mya perna. 
. 33- Mytilus fmaragdinus : fhell nearly triangular, flat- 
tifli; hinge two-toothed in one valve, and one-toothed in 
the other. ' Inhabits Tranquebar: green, and a little per- 
laceous within. " ‘ 
( 3 . Inhabits Guinea; brown, with a green margin, and 
fometimes a few' fpots on the difk. 
34. Mytilus verficolor: fhell nearly triangular, flattifli; 
hinge one-toothed ; margin glabrous, acute. Inhabits 
the fiiores of Guinea, and refembles M. afer. It is three 
inches long, and above two broad ; the fhell covered with 
a brown fkin, under which it is marked with crowded 
dul'-green tranfverfe ftrite, and varied with violet, white, 
and chefnut. Probably a variety of Mya perna. 
35. Mytilus coralliophagus : fliell carinate in the mid¬ 
dle, and crenate at the margin, with an obtufe knob. 
Inhabits the Indian and American Ocean, and perforates 
rocks like a Pholas. About three quarters of an inch 
long. 
36. Mytilus lineatus : fliell triangular and dilated out¬ 
wards, with angular, decuflate, and confluent, lines ; 
hinge tw'o-toothed. Shell minute; yellowifh, with a 
mixture of green ; within a little filvery. 
37. Mytilus faba : fhell oval, rufous, ftriate, with a 
crenulate margin. Inhabits the feas of Greenland, flick¬ 
ing to rocks by a bronzed byflus, or beard ; and is the 
food of the Anas hyemalis and hiftrionica. 
38. Mytilus fluviatilis: fhell thin, flightly wedged, 
within reddifh : beaks recurved and large. Inhabits frefli 
waters of Europe ; refembles M. anatinus, and is proba¬ 
bly not a diftintfl fpecies. 
39. Mytilus fufcus : fliell fmall, oblong, narrow, browm, 
with a very fine tranfverfe ftriae ; one fide emarginate, the 
other rounded ; beaks prominent, curved. 
40. Mytilus mammarius : fhell broad, fliort, and round¬ 
ed behind ; beaks conic, protuberant. 
41. Mytilus Perficus : fhell broad, and covered with a 
rough rugged yellow coat. Inhabits the Perfian Sea: 
thrice as broad as it is long. 
42. Mytilus piftus : fliell broad, very fmooth, flamme- 
ous or rofe-colour, with white bands; beaks obtufe. In¬ 
habits Portugal : thrice as broad as it is long. 
43. Mytilus fafciatus : fliell pellucid, fhining; bluifli, 
with a claret-colour and pale-red band. Inhabits Braiil; 
twice as broad as it is long. 
44. Mytilus undatus : fhell broad, and rounded at both 
ends ; claret-colour, with undulate, bluifli, and greenifh, 
ftriae ; margin ferrate. Inhabits the Portuguefe Sea. 
45. Mytilus purpureus : fliell rounded behind; pale 
fiefli-colour, purple within ; the margin denticulate. In¬ 
habits the fhores of Brafil. 
46. Mytilus faxatilis: fhell ear-fhaped, with granu¬ 
late wrinkles on the outer fize, dilated and rounded. In¬ 
habits Amboyna, flicking to rocks; and is eaten by 
ducks and fwine. Shorter and broader than the joint of 
a finger. 
47. Mytilus argenteus: fliell tranfverfely ftriate, round¬ 
ed at each end, brown, filvery within ; beaks rounded. 
48. Mytilus fulgidus; fliell narrow, lhiriing, blufh-co- 
lour. 
