% 
fremhærer, at hin har en forskjellig formet Mundaabning, 
mere vinklede Vindinger og Ribberne færre og mere fjer- 
nede. Ved Sammenligninger af norske og amerikanske 
Eksemplarer finder jeg ingen nævneværdig Difference i 
Mundaabningens Form og hvad de øvrige Karakterer angaar, 
da er disse stærkt vexlende. Som Regel er Ribbernes 
Antal 14—16, men jeg har Exemplarer for mig med indtil 
20, Faryen er altid rød eller brunlig. Hos Bela nobilis 
har jeg gjort opmærksom paa, at der imellem Ribberne 
er en dyb Indskjæring rundt den vinklede Del af Hoved- 
vindingen og at den transverse Sculptur her viser sig uden 
at være afbrudt af Kjølen. Hos B. harpularia er dette 
ligeledes Tilfælde. Noget andet Slægtskab er der forovrigt 
ikke imellem disse to Arter. 
Hvad angaar det berettigede i specifik at adskille 
nærværende Form fra Montagues B. turricula, da er jeg 
ikke utilbøielig at tro, at vor nordlige Form kun er en 
lokal Varietet og at det maaske vilde være korrektest at 
opføre den som saadan under Montagues Art. 
Allerede Prof. Troschel! har gjort opmærksom paa 
den fra de øvrige Belaer høist afrigende Piltand hos B. 
turricula og Sars? paaviser en lignende Tand hos harpularia. 
Jeg har undersøgt en hel Del Exemplarer baade af 
den hos os forekommende Form og af den sydligere, og 
har i Tab. IX, Fig. 23 og 24 givet en Række Tegninger 
at B. harpularia og i 25 a, b af B. turricula. Teenderne 
er yderst tynde, bladformede og synes at veksle betydelig 
i Form. Muligens er dette dog mere tilsyneladende; thi 
paa Grund af Tændernes Tyndhed vil det mindste Tryk 
af Dækglasset have Indflydelse paa Formen og Tændernes 
vexlende Stillinger giver ligeledes forskjellige Billeder. 
Den Afvigelse, som der derfor viser sig imellem begge 
Arters Tender, kan ikke tillæggesj nogen Betydning i 
specifik Retning. 
Udenfor N. Europa er Arten kjendt fra Grønland og 
N. Amerika, men derimod kan man ikke med Sikkerhed 
notere den under Spitzbergens Fauna. Den norske Exped. 
fandt den ikke der, men vistnok anfører Dr. Jeffreys den 
derfra, dog maa den desuagtet staa tvivlsom, da denne For- 
fatter slaar flere Arter sammen under sin Pleurotoma tur- 
ricula. Prof. Leche angiver den ikke med tilstrækkelig 
Tydelighed fra det Kariske Hav*. ; 
* Gebiss d. Schnecken Bd. 2, Pag. 44, Tab. IV, Fie. 8. 
* Moll. reg. arc. Radula Tab. IX. Fig. 3. 
* Herzenstein (op. c. pag. 688) angiver den derimod fra Mur- 
manske Kysten. 
can species, and points out that the former has a differently 
shaped aperture, more angular volutions and fewer 
ribs, placed also wider apart. On comparing Norwegian 
and American specimens, I do not find any noteworthy 
difference in the form of the aperture, and as regards the 
other characters, they are very variable. Usually, the ribs are 
14—16 in number, but I have specimens before me with 
as many as 20. The colour is always red, or brownish. 
In Bela nobilis, I have pointed out that the interspaces 
between the ribs, round the angulatad part of the Body 
whorl, are concayely excavated and that, there, the trans- 
verse sculpture appears without being interrupted by the 
carina. In B. harpularia this is also the case. Any other 
relationship, however, between these two species does 
not exist. 
As regards the title to separate, specifically, the pre- 
sent form from Montagues B. turricula, I am not indis- 
posed to believe that our Northern form is only a local 
variety, and that it would be, perhaps, most correct to 
retain it as belonging to Montague’s species. 
Prof. Troschelt has pointed out the arrow-tooth in 
B. turricula, which is so different from that of the other 
Belas, and Sars? has shown a similar tooth in harpularia. 
I have examined a large number of specimens, both, 
of the form occurring with us and of the Southern one, 
and in Plate IX, figs. 23, 24 have given a series of illu- 
strations of B. harpularia, and in Fig. 25 a, b of B. tur 
ricula. ‘The teeth are extremely thin, laminate, and appear 
to vary considerably in form. Possibly, however, that is 
more apparent than real, because owing to the thinness of 
the teeth, the least pressure of the cover-glass will have 
an influence on the form, and different positions of the teeth 
The divergence which, 
therefore, appears between the teeth of both species, cannot 
be treated as of any importance in specific consideration. 
Beyond Northern Europe, the species is known from 
Greenland and North America but, on the other hand, we 
cannot state with certainty that it pertains to the fauna 
of Spitzbergen. The Norwegian Expedition did not find 
it there but it is the case that Dr. Jeffreys cites it from 
that locality; it must nevertheless remain doubtful, as that 
Writer includes several species in his Plewrotoma turricula. 
Prof. Leche states, but not which sufficient distinctness, 
that it pertains to the Kara sea®, 
give, also, different impressions. 
* Gebiss d. Schnecken Bd. 2, p. 44, Pl, IV, fig. 8. 
? Moll. reg. are. Radula PI. IX, fig. 3. 
3 Herzenstein (op. e. p. G88) cites it, from the Murman coast. 
