15 
0inene meget smaa, fsestede i ufuldstaendigt udviklede 0ien- 
huler. lste Par Folere med tilspidset Basalplade og korte 
Svober; 2det Par med kort og bredt Blad. 2det Par 
Kjaevefodder uden supplements Gfjelle; 3die Par stserkt 
. udviklet med spadet'ormigt udvidet Endeafsnit. IsteFodpar 
meget kraftigt bygget, for0vrigt af ssedvanlig Form; 2det 
Par tyndt og forlamget, nrnsten npgent, med smal Haand 
og sajrdeles korte Fingre ; belie Par ikke meget lsengere ; de 
2 bagre Par forholdsvis korte, og af robust Bygning. Bag- 
kroplemmernes indre Plade meget kortere end den ydre, 
uden lateralt Appendix og med Undtagelse af lste Par delt 
i 2 Segmenter ; det ydre Segment paa 2det Par hos Hannen 
starlet udvidet og tvelappet. 
Bemaerkninger. Man bar som bekjendt i den nyere 
Tid anseet det for nodveudigt at oplose Slaegten Crangon 
Linne i flere Slaegter; idet Linne’s Slaegtsbegreb ber, som 
i saa mange andre Ti If ad do er bleven oplisiet til Betyd- 
ningen af en distinct Familie ( Crangonidce). De deste 
Carcinologer er saaledes nu enig i at erkjende Slmgterne 
Pontophilus og Sabinea, bvis Arter tidligere beskreves som 
Craugoner. Senere er ogsaa l'oreslaaet en Del andre Slmgter, 
f. Ex. Egeon, Cheraphilus, Nedocrmgon, Paracrangon o. fi. 
Det synes mig nu, at den lamgst bekjendtc arktiske Form, 
Crangon boreas Phipps, viser i mange Henseendcr saa vig- 
tige Forskjellighedcr fra de typiske Crangoner, at den med 
ligesaa stor Bet bpr udskilles fra disse som Typen for en 
egen Slfegt, og jeg bar derfor ber foreslaaet en saadan 
under Bensevnelsen Sderocrangon. Jeg er beri vmsentlig 
bleven bestyrket ved Undersegelsen af nedenstaaende, bidtil 
kun lidet kjendte Form, dor i alt vaesentligt paa det npieste 
slutter sig til Crangon boreas, skjpndt den er sikkert arts- 
forskjeliig. 
Slsegten Sderocrangon udnuerker sig isacr ved de stamkt 
incrusterede og ujevne Integumenter, det licit bvselvede 
Rygskjold, den eiendommelige Form af Rostrum, samtByg- 
ningen af 2det Fodpar og Bagkropslemmernes indre Plade. 
Foruden de 2 ber mevnte Arter tor maaske ogsaa den 
middelbavske Crangon cataphradus Olivi blive at henfore 
til denne Slsegt. 
3. Sclerocrangon salebrosus, (Owen). 
(Pi. ii). 
Syn: A stacus boreas, Tilesiut, Meraoires do l’Acad. Imp. des sciences 
de St. Petersb. Tome V pg. 3‘i2, pi. VII, Fig. 2—5. 
Crangon salebrosus, Owen, Boochcy’s \ oyage. Crust, pg. 88, 
PI. 27, Fig. 1 (teste Middendorf). 
Cheraphilus ferox, G. 0. Sars, Prodromus descriptionis Crust, 
etc. No. 12. 
Artscharacteristik. Habitus og Bygning meget lig 
samme hos Sderocrangon boreas. Rygskjoldet staerkt hvaelvet, 
small, located in imperfectly defined orbitse. First pair o 
antennae with a pointed basal plate and short flagella; se- 
cond pair with a short and broad scale. Second pair of 
maxillipeds without a supplementary branchia; third pair 
very considerably developed, with a spatulate expanded 
terminal division. First pair of legs very powerful in struc- 
ture, for the rest of the usual form ; second pair slender and 
elongate, almost naked, with a narrow hand and exceedingly 
short fingers; third pair not much longer; the 2 posterior pairs 
comparatively short and robust in structure. Inner lamella 
of the pleopods much shorter than the outer, without any 
lateral appendix, and, saving the first pair, divided into 2 
segments; the exterior segment of the same lamella in the 
second pair is, in the male, very considerably expanded, and 
bilobed. 
Remarks. — Of late, it has, we are aware, been 
deemed imperative to break up the genus Crangon Linne, 
into several genera, Linne’s generic division having been 
raised, as in so many other cases, to the rank of a distinct 
family (Crangonidce). Hence, most carcinologists now 
accept the genera Pontophilus and Sabinea, whose species 
were formerly described as belonging to the genus Crangon. 
Still later, a number of other genera have been suggested, 
for example, Egeon, Cheraphilus, Nedocrangon, Paracrangon. 
I am now of opinion, that the long known Arctic species, 
Crangon boreas, Phipps, exhibits in many respects such 
divergent characteristics from the typical Crangonians , 
that it is equally entitled to be regarded as the type of 
a distinct genus, for which I would suggest the name of 
Sderocrangon. In these views I have been chiefly borne 
out on examining the comparatively little known form de- 
scribed below, which, in all essential characteristics, bears 
the closest resemblance to Crangon boreas, though without 
doubt specifically distinct. 
The genus Sderocrangon is distinguished in particular 
by the rough and thickly incrusted integuments, the exceed- 
ingly arcuate carapax, the peculiar form of the rostrum, as 
also by the structure of the 2nd pair of legs and the inner 
lamella of the pleopods. Exclusive of the 2 species recorded 
here, the Mediterranean form Crangon cataphradus, Olivi, 
should, perhaps, be referred to this genus. 
3. Sclerocrangon salebrosus, (Owen). 
(Pi. II). 
Syn. Astacus boreas, Tilesius, Meinoires de l’Acad. Imp. des sciences 
de St. Petersb., Tome V, p. 352, PI. VII, fin-s. 2 — 5. 
Crangon salebrosus, Owen, Beeokey’s Voyage. Crust, p. 88, PI. 
27, fig. 1 [teste Middendorf). 
Cheraphilus ferox , G. 0. Sars, Prodromus descriptionis Crust, 
etc., No. 12. 
Specific Character. — - Habitus and structure closely 
resembling that in Sderocrangon boreas. Carapax extremely 
