69 



Beskrirelse af Hunnen. 



Længden af de største af mig undersogte Ex- 

 emplarer er, niaalt fra Panderanden til Enden af 

 Halepladen, 24 mm. Dog synes det at være meget 

 sjeldent, at den naar en saa bet\'delig Størrelse, og 

 18 — 20 mm. maa ansees for (xjennemsnitsstorrelsen 

 for fuldt udviklede Individer. 



Som lios de ovrige til denne Phyllopodegnippe 

 horende Former, er (se Tab. XI, Fig. 1) Storste- 

 jiarten af Legemet dækket oventil af et bredt, kun 

 svagt livælvet Rygskjold, li vor ved Legemsformen 

 faar et noget tladtrvkt Udseende. Dette Rygskiold 

 er fortil fuldkommen sammenvoxet med Hovedet, 

 livorimod 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 Del af Kroppen at rage frem 

 liagenfor Rygskjoldet i Form af en jevnt af smal- 

 nende, noget cylindrisk Hale, endende med 2 lange, 

 divergerende Vedhæng, Haletraadene, mellem hvilke 

 desuden rager frem en liden median Haleplade. 

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

 Bugflade med sine forskjellige Vedhæng frit for Be- 

 skueren indenfor Rygskjoldets Concavitet. Helt for- 

 til sees en fra Panderanden udgaaende lialvmaane- 

 tormig glat Flade, umiddelbart bag hvilken Folerne 

 og Mnnddelene har sin Plads. Derpaa følger den 

 lange Række af Fodder, der viser et temmelig uens- 

 artet Udseende. Iste Par er ialmindelighed lige ud- 

 strakt til hver Side, saa at det noget overrager 

 Siderandene af Rygskjoldet, medens de derpaa fol- 

 gende 10 Par er mere indadkrummede. dog saaledes, 

 at der mellem dem i Regelen altid tindes et aabent 

 Rum, i Bunden af hvilket Kroppens Bugside sees i 

 Form af en smal rendeformig Fordybning, begrænd- 

 set til Siderne af de re.spective Fodders indadrettede 

 ("oxallapper. Længere bagtil indsnævres dette Rum, 

 og Fodderne ligger her tæt sammen som Bladene i 

 en Bog, aftagende gradvis i Størrelse. Den samlede 

 Fodmasse antager derved Formen af en Ijagtil ven- 

 dende spids Kegle. Den bagerste Del af Legemet 

 er Ilden Lemmer og af simpel cylindrisk Form. 



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

 oval Form, med Sidekanterne jevnt buede og fortil 

 gaaende i et med den ligeledes buede Frontalrand 

 af Hovedet. Bagtil er det noget indsnævret og har 

 i Midten et dybt, vinkelformigt Indsnit, hvis Kanter 

 er bevæbnede med smaa spidse Tagger. Oventil 

 sees i den forreste Del en tydelig transversal For- 

 dybning, Nakkefuren, i Bunden af hvilken der er en 

 afrundet Tværvulst, der antyder Mandiljularsegmen- 

 tet. Den foran Nakkefuren liggende Del repræsen- 

 terer Hovedet, der i Midten viser en stumpt afrun- 

 det Forhoining, paa hvilken de 2 sammensatte Øine 



Description of the Female. 



The length of the largest specimen examined 

 by me measured 24 mm. from the frontal margin to 

 the end of the caudal lamella. It seems, however, 

 very seldom that it attains so considerable a size, 

 and from 18 to 20 mm. must be considered as the 

 average size for fully-developed animals. 



As in the other forms belonging to this group 

 of Phyllopoda, tlie greater part of the body (see 

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

 slightly vaulted carapace, whereby the body acquires 

 a somewhat flattened appearance. This carapace 

 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 body is seen projecting from behind 

 the carapace in the form of an evenly tapering, 

 somewhat cylindrical tail, ending in two long, di- 

 vergent appendages, the caudal filaments, between 

 which there also projects a small median caudal 

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

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

 pendages lies exposed to view within the concavity 

 of the carapace. Right in front, a cres(;ent-shaped, 

 smooth surface is visible, starting from the frontal 

 margin, and immediately behind this are situated 

 the antennæ and the oral parts. Then follows the 

 long row of legs Avhicli present a somewhat hetero- 

 geneous appearance. The first i)air is generally 

 extended equally to both sides, so that it projects 

 a little beyond the lateral edges of the carapace, 

 while the following 10 pairs are more bent inwards, 

 though in such a waj-, that, as a rule, there is an 

 open space between them, at the bottom of which 

 the ventral surface of the body is visible in the 

 shape of a narrow groove bounded laterally by the 

 inwardly inclined coxal lobes of the respective legs. 

 Further 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 the form of a posteriorly pointing 

 cone. The hindmost part of the body is without 

 limbs, and in the form of a simple cylinder. 



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

 broad oval shape with the lateral edges evenly 

 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 small, sharp 

 denticles. In the anterior part above, may be seen 

 a distinct transversal hollow, the cervical sulcus, 

 at the bottom of which there is a rounded trans- 

 verse prominence, indicating the mandibular segment. 

 The region in front of the cervical furrow repre- 

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



