88 Dr. E. von Martens on the Subdivisions of Pinna. 
specimens, the adult states of which are either unknown or de- 
scribed under other names :—P. bullata, Gmel.= P. marginata, 
Lam., Gualt.79C; P. sanguinea, Gmel., Gualt. 79 B; P. vitrea, 
Gmel.; P. papyracea, Chemn. 786; P. sanguinea, Reeve, 62. 
Note 1.—The specimen figured by Reeve (probably the same as 
that upon which the species was based) seems to be the young of 
a larger species very near to P. truncata, which I obtained in Japan 
and deposited in the Berlin Museum. The greater part of the out- 
side is smooth, the radiating striee of the young shell disappearing 
totally in the later parts of the shell; but the concentric striz of 
growth are repeated throughout very distinctly. The ligamental 
(dorsal) margin is nearly straight, the opposite one near the apices 
concave, then convex, the margin opposite to the apices nearly 
straight. The colour of the shell is a dull greenish grey; some 
yellow black-edged spots, visible at the outside, prove, by in- 
spection of the inside, to be caused by an abnormal deposit of shelly 
matter, containing holes, and oceasioned probably by the intrusion 
of some parasite. Length 300, breadth 150 millims. 
Note 2.—Some recent authors name this species P. nigra, Chemn. 
Chemnitz himself, however, called it P. nigra fumigata (the “ black 
smoked ham”’), in opposition to his “red ham” (P. rudis, L.). It 
‘ought to be remembered that Chemnitz uses names agreeing with 
the Linnean rules only for a part of his species, chiefly in the later 
volumes ; but for others he uses names of three or four words, which 
cannot be admitted in our nomenclature. It is true that the name 
and the diagnosis are generally united by him in one body ; but one 
can almost in every case recognize what he intended to be the name 
and what the diagnosis,—first, by the first comma being placed be- 
tween the last word of the name and the first of the diagnosis ; se- 
condly, by the list of species, preceding for each genus the descrip- 
tions of the single species and repeating the names but not the dia- 
gnoses of them. The same remarks apply to Pinna incurva, which 
was named originally by Chemnitz P. cncurvata glabra, for which 
Gmelin substituted the simple word zncurva. 
Note 3.—The margin opposite tothe apices seems to bevery different 
in the figures placed here together ; but it is not improbable that in the 
originals of some of them, especially those which appear transversely 
truncated, the margin is not entire, but was broken and has been 
quasi reintegrated by application of the file ; at least there are many 
specimens treated in this manner in old collections. The first glance 
at the lines of growth will always detect this artifice in a specimen, 
but not always in a figure. 
[To be continued. | 
