434 



PROCEEDINGS OF THE \ \TI<>\ \i. MUSEUM. 



vol. 38. 



Order CLADOCERA. 



Division GYMNOMERA. 



Tribe ONYCHOPODA. 



Genus PODON Lilljeborg, 1853. 



PODON LEUCKARTI (Sars). 



Pleopis leuckarti Sars, Forh. Vid. Selsk. Chrisiiania, 1861, p. 45. 



/'ni/an jin/i/jili, nmides P. E. MiJLLER, Danmarks (ladocera, L867, p. 220, pi. 6, 

 figs. 5 6. 



Podon leuckarti Sars, Forh. Vid. Selsk. Chrisiiania, ISilO, no. 1, p. 14. — Lillje- 

 borg, Nova Aria Elegise Soc. Sci. Upsaliensis, ser. 1, vol. 19, 1901, p. 636, 

 pi. 85, fig. 12; pi. <S6, fig. 1-3. — Apstein, Nordischea Plankton, ( 'ladocera. 

 Kid, L901, p. I:;, fig. 23. 



Female from 0.89 to 1 nun. long, and aboui two-thirds as high. 

 Males slightly smaller. Seen from the side (fig. 10 a, b), both sexes 



are broadly ami evenly rounded dorso- 

 posteriorly. The head has a nearly 

 straight upper contour, about two-thirds 

 as high as long, and nearly one-half the 

 length of the entire body. A prominent 

 convexity below and just posterior to the 

 neck region. Both branches of the two 

 branched antenna' (second antennae) are 

 armed with six seta' each, while both 

 /\ intermedins Lilljeborg, and P. i><>hj- 

 phemoides (Leuckart) have seven seta 1 on 

 one branch and six on the other one. 



Outer process of the first leg with one 

 seta; of second leg w it h one seta ; of third 

 leg with one seta; of fourth leg with two 

 seta 1 . 



The posterior part of the body termi- 

 nates in two long spines. The shell is very 

 transparent, and from grayish yellow to 

 w hitish in color. The so-called aeck gland 

 is situated near the neck invagination. 



Hi marks. — This species was noted in 

 the same collections as those containing 

 Evadru nordmanni Loven, and therefore 



with the same species of Copepoda. 



Occurrence. Surface tidal tows at Bureau of Fisheries wharf. 

 Woods Hole, Massachusetts. Also in ordinary surface tows at 10 

 p. m-. (piiet water and northeast wind; more abundantly at 8 a. m- 

 in sunlight at the same place, August 11, 1!)()!). 



Distribution. North Sea (Timm), May-July; oil' western coast of 

 Europe and the Mediterranean Sea (Lilljeborg). 



FlG. 1'.'. PODOM I.KCt KAIITI. <l ll'l 



VIEW OF female; b, SIDE yikw OF 

 u M.I . 



