69 



Beskrivelse at" Hmiiion. 



Længden af de storste af mit;- uiidersng-tf Ex- 

 emplarer or, maalt fra Panderanden til Enden af 

 Halepladon, 'J4 mm. Bog synes det at være meget 

 sjeldent, at den naar en saa betydelig Storrelse, cig 

 18 — 20 mm. maa ansees for (TJennemsnitsstorrelseu 

 for fuldt udviklede Individer. 



Som hos de ovrige til denne I'liylbijiodegruppe 

 liorende Former, er (se Tali. XI, Fig. 1) Storste- 

 ])arten af Legemet dækket oventil af et bredt, kun 

 svagt hvælvet Rygskjold, hvorved Legemsformen 

 faar et noget tladtrykt Udseende. Dette Rygskjold 

 er fortil fnldkommen sammenvoxet med Hovedet, 

 hvorimod det bagtil kun lost dækker den underlig- 

 gende Krop, som frit kan- bevæges under .samme (se 

 Fig. 3). Sees Legemet ovenfra (Fig 1), viser .sig en 

 større eller mindre iJel af Kroppen at rage frem 

 bagenfor Rygskjoldet i Form af en jevnt afsmal- 

 nende, noget cylindrisk Hale, endende med 2 lange, 

 divergerende Vedhæng, Haletraadene, mellem hvilke 

 desuden rager frem eu liden median Haleplade. 

 Sees Legemet nedenfra (Fig. 2), Ugger hele Dyrets 

 Rugflade med sine forskjellige Vedhæng frit for Be- 

 skueren indenfor Rygskjoldets Concavitet. Helt for- 

 til sees en fra Panderanden udgaaende halvmaane- 

 formig giat Flade, umiddelbart bag hvilken Folerne 

 og Munddelene har sin Plads. Derpaa fdger den 

 lange Række af Fodder, der viser et temmelig iiens- 

 artet Udseende. Iste Par er ialmindeliglied lige ud- 

 strakt til hver Side. saa at det noget overrager 

 Siderandene af Rygskjoldet, medens de derpaa føl- 

 gende 1(1 Par er mere indadkrummede. dog saaledes, 

 at der mellem dem i Regelen altid tindes et aal>ent 

 Rum, i Bunden af hvilket Krop])ens Bugside sees i 

 Form af en smal rendeformig Fordybning, begrænd- 

 set til Siderne af de resjieetive Fodders indadrettede 

 ('oxalla])jier. Læugere bagtil indsnævres dette Rum, 

 og Fodderne ligger lier tæt sammen som Bladene i 

 en Bog, aftagende gradvis i Storrelse. Den samlede 

 Fodmasse antager derved Formen af en bagtil ven- 

 dende spids Kegle. Den bagerste Del af Legemet 

 er udeu Lemmer og af simpel cylindrisk Form. 



Rygskjoldet viser, ovenfra seet (Fig. 1), en liredt 

 oval Form, med Sidekanterne jevnt buede og fortil 

 gaaende i et med den ligeledes buede Fi'ontalrand 

 af Hovedet. Bagtil er det noget indsnævret og har 

 i Midten et dybt, vinkelformigt Indsnit, hvis Kanter 

 er bevæbnede med smaa spidse Tagger. ( )ventil 

 sees i den forreste Del en tydelig transversal For- 

 dybning, Nakkefuren, i Bunden af hvilken der er en 

 afrundet Tværvulst, der antyder Mandibularsegmen- 

 tet. Den foran Nakkefuren liggende Del repræsen- 

 terer Hovedet, der i Midten viser en stumpt afrun- 

 det Forhoining, paa hvilken de 2 sammensatte Dine 



Description of the Female. 



The length of tlie largest S]ierimen examined 

 by me measured 24 mm. from the frontal margin to 

 tlie end of the caudal lamella. It seems, lioweven, 

 very seldom that it attains so considerable a size, 

 and from IS to 20 mm. miist be considered as the 

 average size for fnlly-develo|ied animals 



As in the other forms liclongiug to tliis group 

 of Phyllopoda. the greater part of the body (see 

 PI. XI, fig. 1) is covered above by a broad, only 

 slightly vaulted carapace, whereby the body ac(|uires 

 a somewhat flattened appearance. This cara]ja(.'e 

 is completely united in front with the head, whereas 

 posteriorly it only loosely covers the underlying- 

 body, which can move freely beneath it (see fig. 3). 

 When the animal is viewed from above (fig. 1), more 

 or less of the l)ody is seen projecting from behind 

 the carapace in the form of an evenly tajjering, 

 somewhat cylindrical tail, ending in two long, di- 

 vergent appendages, the caudal filaments, lietween 

 which there also projects a small median cau<lal 

 lamella. When viewed from below (fig. 2), the whole 

 of the animal's ventral surface witli its various ap- 

 pendages lies exposed to view within the concavity 

 of the carapace. Right in front, a crescent-shaped, 

 smooth surface is visible, starting from the frontal 

 margin, and immediately Ijehind this are situateil 

 the antenn æ and the oral parts. Then follows the 

 long row of legs which i>resent a somewhat hetero- 

 geneous ajipearance. The first ]iair is generally 

 extended eipially to both sides, so that it projects 

 a little be\'ond the lateral edges of the carapace, 

 while the following 10 j^airs are more bent inwards, 

 though in such a way, that, as a rule, there is an 

 open space between them, at the bottom of which 

 the ventral surfai-e of the body is visible in the 

 shape of a narrow groove bounded laterally by the 

 inwardly inclined coxal lobes of the respective legs. 

 Fnrthei' back, this space is contracted, and the legs 

 lie as close together as leaves in a book, diminishing 

 gradually in size. The accumulated mass of legs 

 then assumes tlie form of a posteriorly pointing- 

 cone. The hindmost pai't of the body is without 

 limbs, and in the fonn of a sim])le cylinder. 



The carapace, seen from above (fig. 1), is of a 

 broad oval shape with the lateral edges evenlv 

 curved, and continuous! with the likewise curved fron- 

 tal margin of the head. It is somewhat narrowed be- 

 hind, and has, in the middle, a deep, angular inci- 

 sion, the edges of which are armed with snuill, sharp 

 denticles. In the anterior part aljove, may be seen 

 a distinct transversal hollow, the cervical sulcus, 

 at the bottom of which there is a rounded trans- 

 verse jirominence, indicating- the mandibular segment. 

 The region in front of the cervical furrow repre- 

 sents the head, and exhibits, in the centre, a bluntly 



