the Trondhjein Fiord. 17)',) 



egg-bearing male, and Iloek found three such .specimens. On 

 the other lumd, it is not uncommon for animals to be sexually 

 mature before they have attained their full development. It 

 seems ea.sy to account for the more frequent occurrence of the 

 smaller than the larger specimens. This species, like Piioxi- 

 chilidium cucctneuvi, undergoes its metamorphosis within the 

 bodies of Hydrozoa ; these small specimens (P. pygnuea) 

 cannot have long left that shelter, but they have now readied 

 a period of life when they would be exposed to constant 

 danger, and thus comparatively few would live to maturity. 

 The length of the cephalic segment might be expected to 

 increase with growth ; except in the difference of this organ 

 the resemblance of the two is most exact. The terminal 

 joints of the legs are identical in their armature ; the propodos, 

 which is narrower in proportion To its length with increasing 

 growth, has the spines quite similar, and, above all, there is 

 the " thin undivided lamina " occupying the distal portion of 

 the palm, beyond the " row of small anteriorly curved spines." 

 This thin, perfectly transparent, undivided lamina is, I 

 believe, unique, and constitutes a peculiar specific character 

 of Anoplodactylus petiolatus. 



I have also examined two type specimens in Hodge's 

 collection labelled ^^Pallene attenuata, iSeaham, 1862," and 

 *^ Pho.i'ichilidium petiolatunij Seaham, 1863." They are both 

 the present species. 



3. Nymphon mixtum, Kroyer. 



Three specimens in shallow water at Rodberg. I have 

 dredged it also in 100 fathoms off Huglen Island in the 

 Hardanger Fiord. 



4. Nymj)hon leptocheles, G. 0. Sars. 



In 150-250 fathoms at Rodberg. I have also taken it 

 with the last in the Hardanger Fiord ; at Floro, in 25-50 

 fath., and at Dnibak in Norway ; and it was procured by the 

 ' Porcupine ' Exped., 1879, Stat. 47 a, lat. 59° 34' N., long. 

 9° 18' W., in 542 fathoms. 



5. Nymphon Stromii, Kroyer. 



This large species is very frequently met with in the 

 Trondhjem, Bergen, and Hardanger Fiords. It is usually 

 taken in 15-30 fath., but 1 have dredged it once in 100 fath. 



Ann. cfe Maff. N. Hist. Ser. 6. Vol. xiii. 11 



