494 On some rare Crustacea. 



but, so far as we know, this is the first time Lathonura recti- 

 rostris has been observed in a Scottish loch. This Cladocerau 

 appears to be very fragile, for though a number of specimens 

 have been obtained, all are more or less damaged. " The 

 peculiar plates attached to the ventral margin of Lathonura 

 rectirostris^ instead of the usual setae or spines, at once serve 

 to distinguish this species from all other Entomostraca with 

 which we are acquainted " (Rev. A. M. Norman and Dr. G. S. 

 Brady in ' Mon. of Brit. Entom. belonging to the families 

 Bosminidffi, Macrothricidge, and Lynceidaj,' p. 16). The 

 same authors give for this Cladoceran only one locality in 

 the British Islands, viz. Lough Bollard, Connemara. 



Note. — Our friend D. J. Scourfield, Esq., Leytonstone, 

 Essex, has just informed us that he has obtained Lathonura 

 on two occasions, and has seen specimens of it that were 

 collected at one of the excursions of the Quekett Ckib to 

 Staines j and adds, " it appears to be a very rare species." 



EXPLANATION OF THE PLATES. 

 Plate XI. 



Sunaristes paguri, Hesse. 



Fig. 1. Female, lateral view, x 26|. 2. Female antennule, X 127. 

 3. Antenna, x 124. 4. Mandible, x 127. 5. Maxilla, X 127. 

 6. Anterior foot-jaw, X 127. 7. Posterior foot-jaw, X 190. 

 8. Foot of fifth pair, female, X 253. 9. Male, lateral view, 

 X 40. 10. Male antennule, x 127. 



Plate XII. 

 Diaptomus laciniattis, Lilljeborg. 

 Fig. 1. Female, seen from above, X 27. 



Sunaristes. 



Fig. 2. Foot of first pair, X 127. 3. Foot of fourth pair, X 84. 4. Ap- 

 pendages of first abdominal segment, female, X 190. 5. Foot 

 of second pair, male, x 127. 6. Foot of fifth pair and ap- 

 pendages of first abdominal segment, male, X 127. 7. Last 

 three abdominal segments and caudal stylets, male, x 40. 



