NERITA. 395 
regarded as pictorially defined. This conclusion is corroborated 
by the numerals 625 (indicative of vitellus in the tenth edition 
of the ‘Systema’) inscribed upon an example (Gey. Conch. 
pl. 27, f. 296) in the Linnean cabinet. 
As Rumphius had used the word vitellus in allusion to the 
beautifully pated congener which has been so designated by 
most conchologists, it has been generally surmised that the D 
of the reference was a misprint for A (a representation of that 
shell). The “Valvata levis prima sive Vitellus,” however, per- 
chance from having an “umbilico semiclauso,” has been con- 
founded by Linneus with glaucina / in his synonymy ; moreover, 
the Rumphian appellation of the present shell has been written 
in full. The “umbilico equali” has also been objected to, but 
is quite as well (if not better) suited to rufa as it is to the half- 
closed perforation of the rival claimant. 
Mevita alburnren. 
A carelessness, even beyond his wont, has been exhibited by 
Linneus in the synonymy of this species. He has referred us 
to figures of six distinct shells, two of which (those of Regenfuss 
and Lister) do not suit his description in the umbilicus, and 
one (Argenville) in the shape. The other illustrations convey a 
fair impression of the Linnean ideal, a depressed Natica with 
an expanded umbilical lobe: the presence or absence of a sulcus 
upon it, and the distinctions of colouring, &c., would have been 
regarded by him as of mere varietal importance. It is not im- 
possible that the reading of his manuscript was “10, f. V” in 
the reference to Argenville in place of “10, f. T” (the adjacent 
figure), and “‘t. 3, f. 834” in lieu of “t. 5, f. 54” in the reference 
to Regenfuss: in that case we should have had (except as to 
Lister, quoted from its inspection by others) a synonymy in 
harmony with the brief description in the ‘Systema.’ This, 
however, would have comprehended Nat. albumen (Rumph.), 
Nat. didyma of Bolten (Gualt. f. B, central; Arg. f.V.; the 
N. glaucina of Lamarck), and an allied congener without the 
sulcus upon the lobe (Gualt. f. A and lateral B; Reg. f. 34); 
all these forms are present in the Linnean cabinet, but the 
indicative numerals have become obliterated. As they answer 
