362 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
Tarentum Mytilus solen, and gave a tolerable figure. Two years later in the 
second volume of Poli's Testacea utriusque Siciliae the author named the shell 
Tellina togata and figured it. In the same year it reappeared in the English 
translation of Ulysses’ Travels. The Mediterranean species, which must take 
the name of Solemya solen (Ulysses), was named S. mediterranea by Lamarck in 
1818, and was the subject of a remarkable anatomical study by Deshayes in his 
Mollusques de l'Algerie. In this work the shell is admirably figured, and an 
excellent photographic figure of the interior appears in the plates to the Mol- 
lusques marins du Roussillon. 
In this connection it may be stated that no complete account of the hinge of 
this genus is, so far as I have been able to discover, anywhere to be found in 
print. Also that the hinge is by no means uniform in all the species, but by 
means of it they can be divided into groups. 
Solemya australis has a very archaic type of ligament, as perhaps might be 
expected from the archaic features of the anatomy and the situs which the genus 
usually frequent, Yet it is true that the paleozoio relatives of this group have an 
external ligament. In the present species in a fresh state the periostracum and 
true ligament are continuous over the hinge and the gap between the two valves, 
as was the original protoconch in the embryo. The only distinction perceptible 
is that the ligament is a little darker in color. The hinge line is entirely free from 
any trade of provinculum or teeth. The functional part of the ligament is amphi- 
detic, extending on both sides of the beaks and included in a deep groove between 
' two shelly laminae forming the dorsal calcification of the valve, the ligament 
extending beyond the enclosing laminae both before and behind. If dry and 
broken, the section of the ligament has a glassy look, like a piece of glue. Under 
the middle of the ligament and between it and the inner lamina of attachment 
(or nymph) is the resilium, much thicker than the ligament, and of a more fibrous 
constitution and darker color. "The resilium also extends backward of the beaks, 
but not so far as the ligament with which itis intimately cemented. The liga- 
ment extends in advance of the nymph and beaks, throwing down on the inner 
surface of the valve an oval, brown lobe like a dab of varnish. In 9. parkinsoni 
Gray, this lobe is straight, elongated, and narrow. 
The inner lamina or nymph is heavily reinforced with shelly matter, so as to 
bear the strains incident to the resilium which is seated upon it. As the two 
valvés are not so closely adjacent as in most modern bivalves, the resilium is 
visible where it crosses the gap between the two valves to join the opposite 
nymph, and in an unbroken specimen an internal view of the hinge shows in 
brown, against the whiter shelly matter, an X-shaped mass composed of the 
soldered ligament and resilium, the anterior arms of the X being formed by the 
two ligamental lobes above described. The nymph on each side may be sus- 
tained by a prop or rib of shelly matter at cach end, and between these ridges 
may be situated the posterior adductor, but in S. australis only the anterior ridge 
is developed, extended about half-way across the valve, much like the rib in 
Siliqua. The posterior muscular impression is directly behind this rib. In 
