133 
3, Virgus misoolensis Schepman, 
Taf. 13, Fig. 3. 
ünio misoolensis Schepman, Notes from the Leyden Mns., vol. 18, 1896, p. 259, fig. — 
Dronët, Jonrn. de Conch., toI. 45, 1897, p. 125. 
Virgus misoolensis Simpson, Syn., 1900, p. 852. 
Shell elongated, rather compressed, very inaequilateral, the umbones lying at about Ve 
of the whole length of the shell, rather smooth, with numerous fine concentric striae : urn- 
bones little prominent, decorticated in the adult, in half grown shells conspicuous radiating 
folds, extending more ore less over the disk of the shell; moreover a few radiating grooves 
occupy the anterior part of the shell, and microscopic radiating wrinkles of the epidermis 
cover the posterior slope; epidermis reddish-brown in the adult, yellowish olive-green in the 
young ones. Upper margin slightly curved, anterior margin rounded, slightly protuded below; 
ventral margin incurved, posterior margin forming with the upper one a more or less obtuse 
angle, regularly curved above, rounded below and running with a very obtuse angle at the 
umbonal ridge, which is rather obtuse, into the ventral margin. Ligament long, narrow, 
yellowish-brown. 
Nacre bluish white, more iridescent near the posterior part, brownish near the um- 
bones; scarcely more than one short, thick, crenated tooth in each valve; a small knob in 
the left valve may perhaps be conside jed as a second tooth; lateral lamellae; 2 in the left 
valve, one in the right one; they are elongated, slightly curved, rather thick. 
Anterior scars: a large rounded one, which is rather deep, and a much smaller, very 
deep one, just below the tooth; posterior scars very shallow; palliai line distinct. Nacre 
much thickened near the anterior part of ventral margin, forming a callus, which is connect- 
ed with another callus, running from the umbones to this ventral one. 
Long. 65, alt. near the umbones 24, diam. 16 mill. 
Locality. Misool (Hoedt). — In the collection of the Leyden Museum. 
Schepman. 
Schale lang gestreckt, niedrig, zungenförmig, zusammengedrückt, solid. Vordere Ober- 
rand gerade, nach vorn abfallend, mit dem senkrecht abfallend und dann kurz gerundet in 
den Unterrand übergehenden Vorderrand einen deutlichen Winkel bildend. Unterrand hori- 
zontal, fast gerade und nur wenig eingedrückt, Hinterrand von der gerundeten unteren Ecke 
aus senkrecht, von der ebenfalls gerundeten oberen Ecke aus sanfter, gerade ansteigend, mit 
dem geraden, leicht zu den Wirbeln abfallenden hinteren Oberrande einen deutlichen Winkel 
bildend. Winkel niedrig, flach, nicht vorragend, sehr weit vorn, bei der gesamten 
Länge liegend, korrodiert, in der Jugend mit einer aus radialen Falten bestehenden Skulp- 
tur. Aeussere Arealkante niedrig, flach und undeutlich, obere deutlich. Area hoch, drei- 
eckig, zusammengedrückt, Areola hoch, zusammengedrückt. Ligament kurz, fest, vorsprin- 
