59 



Polyartemia forcipata, Fisilior. 



(I'l. l.\ .v; X). 



Polyartemia forcipata, Fischer, Miildemloid's Sibirisolic Keise, 

 Bd. 2. Zoologie, p. 154, Tab. VII, Fig. 24— 28. 



Artscharacter. — Lr-geinet smalt cyliiHliiskt. 

 næsteii jevnt t\-kt lios Hunnen, nd^-et at'snialnende 

 ba,i;-til lios Hannen. Hovedet lio.s Hnnneii iorliolds- 

 vis lidet w^ afrundet fortil, hos Hannen betydelig 

 bredere og endende med 2 stnni])t coniske, nedad- 

 krummede Frontalfortsatser. Halen og Kjonsi'ingeue 

 tilsanimen nepjte mere end halvt saa lang som den 

 fodbærende Del af Kroj)]ien. Ihinncn.s Ægbeholdei- 

 bredt afriindet fortil med et knndefoi'migt Frem 

 s))ring til hver 8ide Hannens ydre Kjiinsvedha'ng 

 simpelt eylindriske og omtrent af Halens halve 

 Længde. Øinene kolleformige, omtrent af Liengde 

 som Hovedets halve Tværdiameter. Forste 1'ar Fo- 

 lere forholdsvis smaa, kortei'e end Øineiie. Anilet 

 Par Følere hos Hininen l)etydelig kortere end Ho- 

 vedet, endende i en triangulær Flig; samme Folere 

 hos Hannen særdeles store, tregrenede, de 2 forreste 

 Grene tangformigt krummede i Enden og fint rili- 

 erede i den indre Kant, den bagei'ste (xren koit, 

 lige nedad rettet og tæt haaret i Enden. Hale- 

 pladerne liredt lancetformige, omtrent doblielt .saa 

 lange som de er brede ved Basis. Legemet gjennem- 

 sigtigt med svagt gronligt, blaaligt eller rodligt 

 Skjær. Hannen sædvanlig lys gulagtig. Hunnens 

 Kjonsringe oventil med 2 iiltramarinblaa kantede 

 Pletter, mellem hvilke er 2 smale Htrii)er af samme 

 Farve, Ægbeholderen orangefarvet nedentil. Hun- 

 nens Længde indtil 1(> mm. Hannens 10 mm. 



Bemærkninger. — Denne eiendommelige Phyllo- 

 pode blev iorst o]idaget under Middendorffs Reise i 

 Sibirien oo- er kortelio; lieskrev(!t under ovenstaaende 

 Navn af S. Fischer, sammen med andre muler Hei- 

 sen indsamlede I'^ntomo.straceer. Den er senere 

 ogsaa gjenfunden af andre Forskere, uden at dog 

 endnu nogeii mere udforlig Beskrivelse er leveret. 



lU'skrivelse af Huiiiioii. 



Længden af Ijegemet, fra 1'anderanden til iMiden 

 af Halebladene, luiar op til K! mm. Dog Huder num 

 den, saaledes som Tilfaddet er med andre i'hyllo- 

 poder, slægtsmoden henge for ilen har naaet denne 

 Storrelse. 



Legenu-t er (se 'Paii. L\. Fig. 1 og 2) slankt, 

 cylindri.skt, og na>sten af ens lii-edcle, dog hus fublt 

 mlviklede Individei' kjendeligt ops\ulmet bagtil i 

 Kjonsregionen. Man kan adskille de samme Krops- 



Polyartemia forcipata. 



(Pl. l.\ c'c X). 



Fischer. 



Poli/artcDiia forcipata, Fischer. Middendorffs .Siberische Keise, 

 Bd. 2. Zoologie, p. 1.54, Tab. Ill, iig. 24—28. 



Specific characters. — lludy narrow cylindrical, 

 r)f almost uniform thickness in the female, taj)ering 

 in the male. Head in female comparatively' snmll 

 and rounded in front, in male consideraitly broader, 

 and ending in two bluntl\' conical, decurved fron- 

 tal ])rocesses Tail and genital segments together 

 scarcely more than half as long as the pedigerous 

 ])art of the body. Marsupium of female broadl3- 

 rounded in front with a nodiform protuberance on 

 each side. I']xternal sexual api)endages of male 

 sim])le c\lindrical, and about half the length of the 

 tail. Ey(>s club-sha])ed, about the length of lialf 

 the transverse diameter of the head. First pair of 

 antenna^ comparatively small, shoiter than tlie eyes. 

 Second ])air of antenna' in female considerably 

 shcu'ter than the head, and ending in a triangular 

 lai)pet; in male very large, tripartite, the two fore- 

 most rami being curved like a forceps at the end, 

 and finely ciliated on the inner margin, the hind- 

 most ramus short, j)ointing straight inwards, and 

 densely haii-y at the extremity. Caudal lamellæ 

 broadly lanceolate, about twice as long as the}' are 

 broad at the base. Body transparent, with a faint 

 gi'een, blue or red tinge: that of male generally 

 pale yellow, (lenital segments of female above with 

 2 angular ultranmrine-blue jiatches, between which 

 there are two narrow stripes of the same colour. 

 Marsupium orange-coloured below. Length of female 

 up to If) mm. that of male, 10 mm. 



Remarks. — This ])ecaliar I'hyllopod was first 

 discovered during Middendorfi's journey in Siberia, 

 and is brietiv described uiuler the above name by 

 S. Fischer, togethei- with othci' Entomostraca col- 

 lected during that journev. It was subsei|ni'ntly 

 also found by other naturalists, notwithstanding 

 whirh, no more detailed description has as yet been 

 furnished. 



Deseriptioii of the Female. 



The length of the body, from the frontal mar- 

 gin to the end of the caudal lamellæ, attains to l(i 

 mm. It is found, however, as is also the case with 

 other PhvUojKida, sexually nuiture long before it has 

 attained this size. 



The body iscr I'l. IX. figs. 1 and 2. is slender, 

 cvlindrical, and ^A' almost uniform breadth through- 

 out, though, in fully develo))ed animals, |icrceptibly 

 distended posteriorly in the sexual renion. The 



