New Crustacea from the Swax River Estuary. 
53 
Pleopocl 1 modified as an accessory sex organ, consisting of two oblong 
plates fitting close together along the median line, narrow in the middle and 
wider again at the extremities, turning out and being rounded terminally. 
The upper surface is produced in a thin plate. A fold on each side distally 
produces a pair of ducts. On the distal rounded portion there are two setae 
apically on each side, and one medianly. Pleopod 2 curved and elongate, 
broader at the base with two apical setae; penial filament apparently two- 
jointed, one joint directed backwards, the other lying in the opposite direc- 
tion, curved and ending in a long styliform extremity grooved along one 
side. A second short round projection lies distally from the penial filament. 
Otherwise the male is like the female. 
From other species brevicornis may be distinguished by the relative 
shortness of the antennae, the shape and armament of the first thoracic 
appendages, the absence of denticles on the pleon. The posterior three 
thoracic segments are not so crowded relatively as in other species, the body 
being relatively elongate. Details of setation and armature on the other 
legs are also specific. 
LITERATURE CONSULTED FOR MTJNN A. 
Barnard, K. H., 1910. Contributions to the Crustacean Fauna of South Africa, 
XII. Ann. S. Afr. Mus., Vol. XXXII pp. 381-543. 
Beddard, F. II., 1886: Isopoda collected during voyage of the Challenger, pt. 3. 
Proc. Zool. Soc., 1886, pp. 97-122 
Chilton, C., 1892: A new Species of Munna from New Zealand. Ann. Mag. Nat 
Hist. (6) 9, pp. 1-12. 
Hansen, H. J., 1916: Crustacea Malacostraca III. Danish Ingolf. Exp., Ill 5 
pp. 1-262. 
Monod, T. : 
1931: Tanaidaeea et Isopodes subantarctiques de la Collection Kohl-Lamen 
du Senckenberg Museum. Senckenbergiana, Band. 13, pp. 10-30. 
1933: Mission Robert Ph. Dolfuss en Egypte Tanaidaeea et Isopoda. Mem. 
Inst. Egypte, T. XXI, pp. 161-264. 
Ricardson, H. : 
1901: Key to the Isopods of the Atlantic Coasts of North America. Proc. 
U.S. Nat. Mus., XXIII, pp. 493-579. 
1905: Monograph of the Isopods of North America. Bull. U.S. Nat. Mus., 
No. 54, pp. 1-797. 
Sars, G. O., 1899. Account of the Crustacea of Norway. 2. Isopoda. 
Stepliensen, K., 1929: Marine Crustacea, Isopoda and Tanaidaeea Zool. of the 
Faroes, XXIV, pp. 1-23. 
Vanhoffen, E., 1914: Die Isopoden der Deutschen Siidpolar-Exp., Vol. XV, Zool. 
VII, pp. 447-598. 
Wahrberg, 1930: Sveriges Marina ocli Lacustra Isopoder. Goteborg. K. Yet. 
o. Yitt. Samh. Handl., Ser. B, I. 9., pp. 1-76. 
