PARANASPIDES AND KOONUNGA 



I!/ 



and the modification of the endopodites of the first two abdominal 

 appendages in the male to form a copnlatory organ. 



A type of a new genus of this family was found by me in the 

 littoral zone of the Great Lake of Tasmania at an elevation of 

 3700 feet, and named Paranavpides lacustris. 



This little shrimp (Fig. 78), which does not appear to grow 

 to more than an inch in length, is totally different in appearance 

 from Anaspides, being pale green and transparent, with a very 

 marked dorsal hump as in Mysis, to which it bears a very 



FIG. 78. Paranaspides lacustris, x 4. a 1 , a?, First and second antennae ; Ab.l, first 

 abdominal segment ; ep, epipodites or gills on the thoracic legs ; md, mandible ; 

 Pl.l, first pleopod ; T, telson ; Th.S, eighth free thoracic segment ; U, nropod, or 

 sixth pleopod. 



striking superficial resemblance. It leads a more active swim- 

 ming life than Anaspides, and with this habit is correlated the 

 flexure of the body and the greater size of the tail-fan and the 

 scale of the second antenna. The mandible is peculiar in being 

 furnished with a four-jointed biramous palp, while that of Anas- 

 pides is three - jointed and uniramous, and the first thoracic 

 appendage is provided with a setose biting lobe on the ante- 

 penultimate joint, thus more resembling a maxillipede. In other 

 respects it agrees essentially in structure with Anaspides. 



Fam. 2. Koonungidae. The sole representative of this 

 family, Koonunga cursor, has been recently described by Mr. 

 0. A. Sayce, 1 of Melbourne University, from a small stream some 



1 The J'ii-forinn Naturalist, xxiv., 1907, p. 117. 



