53 



Tester (Tab. VI, Fig. 11, t) liar Fonnen af et 

 I'ar tbilioklsvis smaa, i^ækformige Organer, der, uligt 

 lixad Tilfæltlet er med Ovarierne, ikke .<tr;ekker sig 

 ind i Forkroppen. idet de fortil knn rækker til l>e- 

 g_yiidelsen af forreste Kjonsring. Iivorinio<l dere.-; 

 liagrt' rils]iidsede Ende strækker sig niei'i' (dier min- 

 dre ind i Iste Bagkropssegmeiit. 1 nogen Afstand 

 fra den forreste Ende udgaar nedad og bagtil Saed- 

 li'deri-n, der begynder med et noget Idæreformigt 

 ndvidet Farti, forestillende et Slags Sa^llieliolder. 

 Ved Basis af de ydre Kjonsvedlia-ng indsna'vres 

 detir 1'aiti pliids(digt til en trang Kanal, der gjor 

 i'n stærk Bugtning inden den tra-iler ind i selve 

 Kjnnsvedliænget (p). paa hvis Spids den ndmunder. 

 S]ii-rnia bestaar (se Fig. 12) af smaa klare Celler 

 med tydelig Kjerne, iniellem hvilke sees en Del 

 endnu mindre og mere iigjeiinemsigtige Smaakngler. 



Udvikling — Jeg har desværre ikke havt An- 

 Icilning til at fortolge den lude I^dvikling af nær- 

 værende Fonn. men har ilug Icilighedsvis paatniffet 

 en Del Udviklingsstadier, livoraf jeg hei' kortidig 

 skal omtale nogle. 



Det tidlig.ste Larvestadium, ji'g har tiindi't. rv 

 afbildet Tah. VIII, Fig. 15, og maa na-rmest dia- 

 racteriseres som et 3fetanai<plruK-St(i(H)im, forsaavidt 

 som der allerede er tydelige Anlæg til 7 Par Lem- 

 mer bag de egentlige Munddele. Det ægte Xauplins- 

 Stadium er, som hekjendt, ndmærket ved Tilstede- 

 værelsen af knn 3 Par Lemmer, nfiiilig de 2 Par 

 Folere og Mandibnlarfodderne. og i dette Stadinm 

 forlader nærværende Form. som de Heste ovrigc 

 1'hyllopoder, Ægget. 



Legemet er i det her omhandlede Stadium af- 

 langt ])æreforniigt, gi-advis afsmalnende bagtil og 

 stumpt afrundet fortil, uden tyd(dig Begra^ndsning 

 af Hoved, l\'ro]i og Hale. De sammensatte Mine or 

 endnu ikke udviklede. og knn det enkle Hie tilstede 

 i Midten helt fortil. Iste Par Folere er enilnu gan- 

 ske korti', men rager tydeligt frem lort il og t'V |iaa 

 Spidsen udrustede med lignende Vedhæng som hos 

 det voxne Dyr. 2det Par Folere er meget forskjel- 

 lino ti'a samme hos det voxno D\"r, og ud\ikledf til 

 niægtige Svomme(ji'ganer eller Aarer. De udsprin- 

 ger, nogt't ventralt, til hver Side at den foi-reste 

 Drl a t' l.fgemet, lige bag Iste Par. og er ialmiudr- 

 lighi'd rotte<Ie lige udåd. Man kan ]iaa doni ad- 

 sk'ille I'll tyk og boielig, med talrige Musklei' tyldt 

 liasahhd idler Skaft, og 2 ulige udvikledi- (irene. 

 Skaftet er at oylindiisk Form og viser Heri' cii'eu- 

 here Indsuoringer som pu Antydniiig til Leddeling. 

 Det udseuder indad 2 mod JIundaabuingen rottede 

 l"\)rtsatser, livoraf den ydre, der n(ls]iringer nær 

 Fnden af Skaftet, har Formen af en grov. jiigformig 

 l)orste, cilieret i sin ydre Del, medens den indre i'r 

 klovet i Enden til 2 rilierede Borstei'. Under .\arer- 

 nes Beva-gelser bliver disse Fortsatser afvexlende 



The testes (Pl VI. Hg. 11, t) are in the form 

 of a pair of comparatively small bag-like organs, 

 whieli, unlike the ovaries, do not extend into the 

 anteri(jr division of the body, but only as far for- 

 ward as the beginning of the foremost genital segment. 

 Their ])osterior pointed ends, on the other hand, 

 extend nnjre or less into the 1st segment of the tail. 

 At some distamr from the antei'ior end issne.s, in a 

 downward and baikward dirertion, the spermatic 

 duct, beginning with a bladder-like enlarged portion, 

 representing a kind of seminal vesicde. At the base 

 of the external sexual a]i]/endage, this part snddenh- 

 contracts to a narrow channel, whiidi makes a sharji 

 curve before it actually enters the sexual ap])en- 

 dage (p) at the point of whi(di it discharges itself. 

 The speini (see tig. 12) consists of small, clear cells 

 with distinct lundei. among which there are a few 

 still smaller and uioi'c opaipie spherirles. 



Development. — 1 have unfortnnately had no 

 op])ortnnity nt' Inllowing the whole course of devel- 

 opment of the jiresent form, but have, howevei", 

 occasionally come across certain stages of develop- 

 ment, some of wlii(di 1 will now briefly mention. 



The earliest larval stage that I have found is 

 represented on I'l. \'lll, tig. 15, and mav be best 

 characterized as a unluiumpUiis sfadiio», in as much 

 as there are distinct indications of 7 pairs of limbs 

 beiiind the oral region pi'oper. The true nau])lius 

 stadinm, as is \\(dl known, is distinguished hx the 

 ])resenc(> of only 3 ])airs ot' limbs, namely, the 2 pairs 

 of antenna* and the mandibular legs, atid at this 

 stage, the pi'csent form, like most other Phvllopoda. 

 leaves till' egg. 



In the stage now under consideration, the bod\' 

 is oblong. ]iyriform, gradually narrowing posteri<trlv 

 and bluntlv rounded anteriorly, without anv distinct 

 division into head. liod\' and tail. The eumjmund eves 

 are not \'ct developed, and only the ocellus is ])resent 

 ill the middle in front. The tirst ])air of antenna* are 

 as yet i|iiite short, but distiiictlv project in front, and 

 are armeil at the jioint with appiMidages similar to 

 those in the full-grown animal. The second pair of 

 antenna' are \ery ditlereut from that ]iair in the tull 

 grown animal, and have the character of jiowertiil 

 natatory organs, or oars. They have their origin a 

 little ventrally at each side of the anterior ])art of 

 the liody, just behind the tirst jiair, and generally 

 point straight out. A thick, Hexible basal part or 

 scape, tilled with numerous muscles may be distin- 

 guished, and 2 unei|ually developed i-ami. The scape 

 is cylindi'ical in fiu'ni. and exhibits several circular 

 constrictions as an indication of articulation. It 

 sends out inwards, tuwards the oral aperture, 2 |iro- 

 jections of which the outer one, which springs from 

 near the end ot' the sca]ie, has the form of a coarse 

 spilce-like bi'istle, ciliated on the outer ]iart : while 

 the inner one is cloven at the end into 2 ciliated 



