FRESHWATER CRUSTACEA OF TASMANIA. 85 



Order COPEPODA. 



Family Diaptomidj;. 



Genus Boeckella. 

 Boeckella, Guerne & Richard, Memoires de la Societe Zool. France, vol. ii. (1888) p. 151 ; Davay, 

 Term&sz. Fiizetek, Bd. xxiv. p. 1, and Bd. xxv. pp. 101, 436; Mrazek, Ergeb. Hamburg. 

 Magalh. Sammel. Lief. 6 (1902). 



This genus hitherto consists of several species from Patagonia and temperate 

 S. America, B. triarticulata, Thomson, from New Zealand, B. robusta, Sars (Archiv for 

 Math, og Naturvid. Christiania, xviii.), and B. minuta, Sars (loc. tit.), from S. Australia. 

 It differs from Diaptomus in several quite constant characters, especially in the con- 

 formation of the last pair of limbs in the male. The antennae, mouth-parts, and other 

 limbs are built very much on the Diaptomus plan. 



The genus appears to be entirely confined to the temperate Southern Hemisphere. 



Boeckella insignis, sp. n. (PI. 17. figs. 4-12.) 



Female. — The anterior portion of the body is cylindrical ; the head and first segment 

 fused with it are equal to the succeeding anterior segments. The fifth segment is small, 

 with inconspicuous lateral prolongations which do not project far over the abdominal 

 segments. 



The first abdominal segment is not swollen in the middle. The abdomen consists of 

 3 segments. 



The first antenna consists of 24 joints. The second antenna, mandible, maxilla, and 

 first maxillipede have the form shown in PI. 17. figs. 7-10. 



The last leg has the form shown in PI. 17. fig. 11. It closely resembles that of 

 B. robusta, Sars. 



The uropods bear 5 setae each, exceeding in length the uropods and the last two 

 abdominal segments (PI. 17. fig. 5). 



Length 2 mm. 



Colour. Green. 



Male. — The male is a good deal smaller and has a narrower body. The fifth segment 

 has very small lateral projections. The abdomen consists of 5 distinct segments, not 

 counting the uropods (PI. 17. fig. 5). The last pair of legs have the form shown in 

 PL 17. fig. 12. The right limb has the external ramus biarticulate, with rather a short 

 claw. The left limb has the external ramus uniarticulate, with a longer claw. They 

 resemble closely those of the male B. robusta, Sars. 



The first antenna, which is distinctly geniculated, has 23 joints (PI. 17. fig. 6). 



Occurrence. Among weed in Lake Dulverton. 



Boeckella longisetosa, sp. n. (PL 17. figs. 13-17.) 



Female. — The head and first segment fused with it are shorter than siicceeding anterior 

 segments. The fifth segment is fairly large, with fairly conspicuous lateral projections 

 which are distinctly bilobed, the outer lobe being spiniform, the inner rounded. 



The first abdominal segment is rather swollen in the middle, and the abdomen consists 



SECOND SERIES. — ZOOLOGY, VOL. XI. 12 



