66 
13. Sphyrapus serratus, G. 0. Sars, n. sp. 
(PI. XXI). 
Sphyrapus serratus, G. 0. Sars, Revision af Gruppen Isopoda ehelifera, 
PR. 20. 
Artscharacteristik. Legemet hos Hunnen neppe 5 
Grange saa langt som bredt, hos Hannen betydelig smaekrere. 
Pandepladen meget bred, horizontal, i Midten uddraget i 
en stui np 4-tandet Spids. Sidste Forkropssegment betydelig 
kortere end de ovrigc. Bagkroppens 5 forste Segmenter 
med udstaaende, triangulsert tilspidsede Epimerer. Sidste 
Segment stumpt tilrundet. Ingen 0ine. Iste Par Foleres 
Basalled meget stort, udvidet paa Midten, med 4 Burster 
i den ydre Kant; den indre Svobe ganske lcort, 3-leddet, 
den ydre lios Hunnen 5-leddet, hos Hannen 7-leddet. Sax- 
fodderne kraftigt udviklede, med stserkt opsvulmet Haand, 
Tihialleddet hos Hannen lamgere end Tarsalleddet. Grave- 
fpddernes niestsidste Led hos Hunnen bevsebnet med 3 
stcerke Torner i den indre Kant. Halevedlucngene neppe 
kengere end Bagkroppen, med den ydre Gren meget liden 
og 3-leddet, den indre 10-leddet. Farven ensformig livid. 
Laengden 5 — 6” ,m . 
Findesteder. Stat. 40, 51, 353. 
Bemuerkninger. Nservaerende Art viser en saa paa- 
faldende Lighed med den af mig tidligere characteriserede 
norske Art, Sph. anomalus, at jeg i lang Tid kun holdt 
den for en Yarietet af samme. Ved den noiere anatomiske 
Undersogelse, jeg senere bar anstillet over begge disse 
Former, bar jeg dog fundet visse constante Forskjollighoder 
saavel hos Hun som hos Han, der gjor det npdvencligt at 
skille dem som distincte Arter. Et meget lot opfatteligt 
ydre Kjendennerke for nservaerende Art er de til Siderne 
stserkt udstaaende og triangulsert tilspidsede Epimerer paa 
Bagkroppens 5 forste Segmenter, hvilket bar givet Anled- 
ning til Artsbensevnelsen. Hos Sph. anomalus er disse Seg- 
menter til Siderne stumpt afrundede, og hele Bagkroppen 
synes derved ogsaa her betydelig smalere. 
Beskrivelse af Hunnen. Legemet er (se PI. XXI, 
Fig. 1 og 2) noget. nedtrykt og jevnt afsmalnende bagtil, 
med den storste Brede, der fabler over lste trie Forkrops- 
segment, noget starve end Vs af Laengden. 
Integumenterne er temmelig haarde, glatte og glind- 
sende, samt uden nogen bemaerkelig Haarbessetning, naar 
afsees fra Lemmerne. 
Det forreste Kropssegment, der kun uegentlig kan be- 
najvnes Hovedet, da det i sig tillige indbefatter det lste 
fodbserende Segment, er meget stort, dannende et Slags 
Rygskjold (carapax) af triangular Form, med den stprste 
Brede, der omtrent er lig Laengden, i sin bagerste Del. 
Fortil gaar det ud i en bred, horizontal Pandeplade, der i 
Enden er udtrukket i en kort stump Spids besat med 4 
smaa Tien der (se Fig. 4). Yed Basis af denue Pandeplade 
og indtagende Sidchjurnerne af Hovedskjoldet sees 2 smaa 
13. Sphyrapus serratus, G. 0. Sars, n. sp. 
(PI. XXI). 
Sphyrapus serratus, G. O. Sars, Revision af Gruppen Isopoda ehelifera, 
p. 20. 
Specific Character. — Body in female scarcely 5 
times as long as broad, in male much more slender. 
Frontal plate exceedingly broad, horizontal, produced in 
the middle to an obtuse four-toothed point. Last thoracic 
segment considerably shorter than the others. Five first 
segments of abdomen with projecting, triangular, acuminate 
epimora. Last segment obtusely rounded. Xo eyes. Basal 
joint of 1st pair of antenme exceedingly large, dilated in 
the middle, with 4 bristles on the outer margin; inner 
fiagellum very short, three-jointed; outer in female five- 
jointed, in male seven-jointed. Ghelipeds powerfully de- 
veloped, witli the hand greatly swollen; tibial joint in male 
longer than tarsal joint. Penultimate joint of fossorial legs 
in female armed with 3 strong spines on the inner margin. 
Caudal appendages scarcely, if at all, longer than posterior 
division of body, witli the outer branch exceedingly small 
and three-jointed, the inner ten-jointed. Colour a uniform 
white. Length from 5 to 6’ nm . 
Locality. — Stats. 40, 51, 353. 
Remarks. — The present species exhibits so striking 
a resemblance to the Norwegian I had previously described 
under the name of Sph. anomalus, that I long held it 
to be a mere variety of that form. Meanwhile, a closer 
anatomical examination of both these animals has brought 
to light divers constant deviations both in the female and 
the male, that render it necessary to establish them as 
distinct species. A readily appreciable outer characteristic 
in the present form are the triangularly pointed epimera 
on the 5 first segments of the abdomen, prominently pro- 
jecting toward either side, from which indeed the specific 
designation is derived. In Sph. anomalus, these segments 
are at the sides obtusely rounded; and hence the whole 
posterior division of the body in that species too, appears 
considerably more slender than in the present form. 
Description of the Female. — The body somewhat 
depressed (see PI. XXI, figs. I , 2) and tapering gradually 
backward, with its greatest breadth, that occurs across the 
1st free thoracic segment, slightly exceeding one-fifth of the 
length. 
The integuments comparatively hard, smooth, and 
lustrous, as also without any covering of hair, except on 
the appendages. 
The most anterior segment of the body, which in 
anything but a strict sense can be termed the head, com- 
prising as it does also the 1st pedigerous segment, is ex- 
ceedingly large, constituting a kind of carapax, triangular 
in form, its greatest breadth about equal to the length across 
the posterior portion. Anteriorly, it projects as a broad, 
horizontally extending frontal plate, which, at the extremity, 
is produced to a short, obtuse point, beset with 4 small 
teeth (see fig. 4). At the base of this frontal plate, and 
