1908] Decapod Urustaceans. 67 
what inwards from the inner edge of the endopod. The specimens 
showing this form of appendage were of different sizes and appear 
to present no specific differences from typical specimens of P. annu- 
licormis (MontaGun).” Carman depicts an endopodite of this cha- 
racter and it appears both from his drawing and description that 
he has had before him forms absolutely corresponding to those 
found among my material and depicted in fig. 5, III. It is pos- 
sible,” says Carman, "that the characters mentioned may be due 
to immaturity, but unfortunately the material at my disposal is not 
suffieient to elucidate this point.” 
It seems however hardly credible that these males should not 
have reached maturity and that this is the reason for the shrunken 
appearance of the organ of copulation: and it becomes all the more 
improbable when we consider that we are in possession of å group 
of smaller males with strongly developed organs of copulation. 
These smaller males, about 35—40 mm. long, are supposed 
from their size not to have previously reproduced their kind. 
I consider that we have here an analogous case to what has 
been observed in the North-American cambarus species. HAGEN 
has show.» concerning them that there are regularly found two dif- 
ferent forms of males, one form with a strongly developed organ 
of copulati>n, and the other form with a slightly developed organ. 
According to Faxon's observations the explanation of this is that 
males of the first form (with a strong organ of copulation) after 
the pairing-time undergo å moult, after which they assume the 
appearance of the second form. 
In none of our other Pandalidae have I succeeded with the 
material we now possess in finding å corresponding *dimorphism”, if 
I may use the term,') to what we observe in Pandalus annulicornis. 
Pandalus propinquus G. 0. SARs. 
In the fiords close to Bergen (Byfjord, Moldøen, Radøfjord, 
Herløfjord, Osterfjord, Nordfjord, and several others) P. propinquus 
has been found in considerable abundance. In some localities such 
1) While correcting the proof of this paper Dr. Uarman has informed me 
that a similar series of phenomena has been recently described in certain Bra- 
chyura by Mr. G. SmirH (G. SmitH: "On High and Low Dimorpbism with an 
account of certain Tanaidae of the Bay of Naples. Mitth. zool. stat. Neapel 1905). 
34 
