T. C. Russell—The Jordan-Arabah and the Dead Sea. 387 
joint, which is slender and pointed, and has the caudal lamelle of the 
6th segment lying close beside it; the outer one of which is marked 
by a transverse articulation near its lower extremity. The false 
abdominal feet, with their basal joints and their bifid multiarticu- 
late appendages (exopodite and endopodite), are also clearly seen. 
In 1866 I described a new species of Alger from the Lias of 
Lyme Regis, Dorset (see Guot. Mac. 1866, p. 10, Pl. I.). This 
specimen, which I named Ager Marderi, is much larger, and alto- 
gether more robust, with shorter and stouter limbs than that now 
under consideration. Mr. Brodie’s specimen is not only smaller, but 
the limbs are much longer and more delicately slender.’ 
’ Having many beautiful examples of these elegant Crustaceans 
from Solenhofen now before me (part of the grand collection formed 
by Dr. Haberlein, and purchased of him in 1863 for the British 
Museum), I have been able to study and compare this fossil from 
Wilmcote with these, and also with that from Lyme Regis referred 
to above, and I am of opinion that it is specifically distinct from all 
these, although the species have, as a whole, a well-marked generic 
facies. I propose, therefore, to name this form ger brodiei, in 
honour of my valued geological friend, the Rev. P. B. Brodie, whose 
labours in the Liassic beds of Warwickshire and elsewhere, extending 
over half a century, have resulted in a large accession of interesting 
and beautiful Arthropoda to the Liassic Fauna of Britain. 
II.—Tue Jorpan-AraBan Depression AND THE Drap Sma. 
By Israzt C. Russet, 
Of the United States Geological Survey (Appalachian Division of Geology), 
Department of the Interior, Washington, D.C., U.S.A. 
(Concluded from the August Number, p. 344.) 
Lacustrine History of the Dead Sea Basin. 
HE occurrence of numerous terraces on the mountain slopes over- 
looking the Dead Sea has been reported by several observers, 
but no accurate measurements of their elevations or definite correlation 
of the terraces on the opposite slopes of the depression, seem to 
have been attempted. In the central part of the Wady Arabah 
on the west flank of the promontory known as Samrat el Fedan, 
a terrace, or perhaps more properly a gravel bar, has been observed 
by Hull? at an elevation of about 1300 feet above the Dead 
Sea. This is apparently a definite record of the surface level of the 
Dead Sea during a former period. On the sides of the Jordan valley 
the terraces range in height from a few feet to 750 feet above the 
river. The measurements reported show great variation due princi- 
pally to an inclination of the surfaces of the terraces, towards the 
centre of the valley, but indicating also that they are not horizontal in 
the direction of drainage. The terraces of the Jordan valley, although 
1 Tn describing the Lyme Regis fossil, I erroneously spoke of the long spinigerous 
maxillipeds as the first pair of thoracic legs. 
2 Geol. and Geog. of Arabia Petrea, Palestine, etc., page 87. 
