60 



afsnit som hos Branchinecfa, skjoiidt deres indliyr- 

 des Længdeforhold ei- temmelig forskjelligt. 



Hovedet er forholdsvis af ringe Størrelse og 

 stiimpt afrundet fortil. Det afgrændser sig skarpt 

 fra Nakkesegmentet, der til hver Side viser Skal- 

 kjertelen meget tydeligt. Tranens er stærkt for- 

 længet, regelmæssigt eylindrisk, og delt i ikke min- 

 dre end 19 vel begrændsede Segmenter, hvert bæ- 

 rende et Par Branehialfodder. 



Bagkroppen ndmærker sig i hoi Grad ved sin 

 korte og plnmpe Form, idet den neppe indtager 

 mere end Vs af Kropslængden. Kjonsringene er 

 fnldstændig sammensmeltede saavel indbyrdes som 

 med den bagenfor liggende Del af Halen, paa hvil- 

 ken alene det bagerste Segment er tydeligt be- 

 grændset. Hele dette Parti har, seet ovenfra (Fig. 

 2), en næsten pæredannet Form, idet det fortil er 

 stærkt fortykket og ligesom opblæst, med en afrnn- 

 det knndeformig Protnberans til hver Side, medens 

 det bagtil gradvis afsmalnes. Breden over den for- 

 reste Del af dette Afsnit er mere end dobbelt saa 

 stor som Breden over selve TriTneus. Sees Dyret 

 fra Siden (Fig. 1), viser sig Størsteparten af den 

 ventrale Side af dette Parti optaget af den volumi- 

 nose Ægbeholder, hvis forreste Del er særdeles 

 stærkt hvælvet, medens den bagtil kuji rager ube- 

 tydeligt frem i Form af et kort koniskt Frem- 

 -spring. Paa Enden af dette Fremspring lindes den 

 ydre Aabning for Ægbeholderen, som hos Branchi- 

 Hf-cta, begrændset af 2 vertikale mod hinanden be- I 

 vægelige Læber, hvoraf den øver.ste er den største 

 og ender i en tilspidset Knude (se Tab. X, Fig. 12). 

 Halepladerne (se Tab. IX, Fig. 6) er forholdsvis 

 korte, neppe mere end dobbelt saa lange som de er 

 brede ved Basis, og viser en bredt lancetdannet 

 Form, med Spidsen smalt afrundet. De er hver 

 kantede med omtrent 19 cilierede Borster der sue- 

 cessivt tiltager i Længde mod Spidsen. 



Øinene (Tab. X, Fig. ], o) er forholdsvis korte 

 og tykke, neppe længere end Hovedets halve Brede, ! 

 og af den sædvanlige pæredannede Form, med Øie- 

 globen jævnt afrundet. Øiepigmentet er morkt, dog ' 

 hos det levende Dyr med et tydeligt purpurrødt 

 Skjær, og de enkelte Synselementer vel udviklede. 

 Det enkle Øie sees som en tydelig mork Plet i Mid- 

 ten af Hovedets Pandedel. 



Forste Par Følere (Fig. 1, a', Fig. 3) er for- 

 holdsvis betydelig kortere end hos Branchinecfa, 

 neppe halvt saa lange som Øinene, men viser for- 

 ovrigt en meget lignende Bygning, og bærer jjaa 

 Spidsen de sædvanlige Lugtepapiller og Foleborster. 



Andet Par Følere (Fig. 1, a-) er ligeledes min- 

 dre end hos Branchinecta, og har Formen af 2, som 

 det .synes, fuldkommen ubevægelige trekantede Flige, 



same body-divisions can be distinguished as in Bran- 

 chinecta, although their mutual relations as to length 

 are rather different. 



The head is comparatively small and bhintly 

 rounded in front. It is sharply defined from the 

 cervical segment, which shows the shell-gland on 

 each side very distinctly. The trunk is greatly 

 elongated, regularly cylindrical, and divided into no 

 less than 19 well-defined segments, each bearing a 

 pair of branchial legs. 



The posterior part of the body is highly remar- 

 kable for its short and stout form, constituting, as 

 it does, scarcely Vs of the length of the body. The 

 genital segments are completely coalesced, both 

 mutually and with that part of the tail posterior 

 to them, in whicli only the hindmost segment is 

 distinctly defined. The whole of this part, seen 

 from above (fig. 2), is almost pyriform, being very 

 much thickened in front, and as it were inflated, 

 with a roixnded, nodiform pnituberance on each side, 

 while posteriorly it tapers gradually. The In-eadth 

 of the front part of this section is more than double 

 as great as that of the trunk itself When the 

 animal is seen from the side (fig. 1), the greater 

 part of the ventral side of this region appears to be 

 occupied by the voluminous marsupium, the anterior 

 part of which is boldly convex, while the posterior 

 end projects only slightly in the form of a short, 

 conical prominence. At the end of this prominence 

 is seen the external opening of the marsupium, 

 bounded, as in Branchinecta, by 2 movable lips, the 

 upper of which is the larger, and ends in a pointed 

 nodule (see PI. X, fig. 12). The caudal lamellæ 

 (see PI. IX, fig. 6) are comparatively short, being 

 scarcely more than double as long as they are broad 

 at the base. They exhibit a broadly lanceolate shape 

 with the point narrowly rounded, and are each 

 fringed with about 19 ciliated bristles, which suc- 

 cessively increase in length towards the point. 



The eyes (PI. X, fig. 1, o) are comparatively 

 short and thick, scarcely longer than half the 

 breadth of the head, and of the usual pyi'iform 

 s]ia]>e, with the eye-ball evenly rounded. The pig- 

 ment is dark, thougli with a distinct tinge of crim- 

 son in the living animal: the visual elements are 

 well-developed. The ocellus is observable as a dis- 

 tinct dark spot in the centre of the frontal part of 

 the head. 



The first pair of antenuæ (figs. 1, a ' and 3) are 

 comparatively mucli shorter than in Brnncltinecta, 

 being scarcely half as long as the eyes, but in 

 other ways exhibit, a very similar structure, and 

 cany at the extremity the usual olfactory papillæ 

 and sensory bristles. 



The second pair of antennæ (fig. 1, a") are also 

 smaller than in Branchinecta, and have the form of 

 2 apparently perfectly immovable triangular lappets 



