250 Prof. M'Intosli's Notes from llie 



more satisfactorily made out since the labours of Ehlers and 

 Clapaibde enriched the subject. The complexity, in the case 

 of such species as Nereis Damerilii^ is sufficiently known, 

 though perhaps it is less difficult to distinguish the various 

 forms in this species than in others. Most of the Nereids 

 frequent tubes of one kind or other. 



At St. Andrews the cosmopolitan Nereis jielag lea appears 

 to show a heteronereid condition only in the male, the female, 

 liowever, having a special coloration at the breeding-season ; 

 yet Ehlers records a lieteronereid female. No finer examples 

 of this species have been found than at St. Andrews, though 

 it rai'ges from Greenland to Japan. Those from tlie Channel 

 Islands are smaller than those in the north. The Nereis 

 cuhrifera of Grube is very generally distributed both on the 

 .eastern shores of Scotland and in the south, as at Plymouth, 

 Polperro, and the Channel Islands. Its value as bait causes 

 it to be more readily observed. The opitocous condition Is not 

 frequent. 



Jt is long $,mc& Nereis irrorata, Malmgren, was procured in 

 the Channel Islands (1868), and, as shown in the collection 

 of the British Museum, at Polperro and elsewhere, and 

 Mr. Allen finds it plentiful at Plymouth. Nereis Alarionii, 

 Aud. & Ed., is al.'^o a stiictly southern form, occurring on 

 the shores of France and the Channel Islands. It does not 

 seem to have been procured at Plymouth. 



No more conspicuous species occurs in the south than 

 Nereis Dumerilii, Aud. & Ed., and it is also abundant in the 

 Avest as well as not infrequent in the east. A species which, 

 in its ordinary form, presents the separate sexes, which may 

 be hermaphrodite, or shows the pelagic transformation in both 

 sexes, cannot be otiierwise than conspicuous, especially in the 

 laminarian region and deeper water. 



Nereis diversicolor, O. F. M tiller, again, is abundant on 

 various parts of the coast — from the northern to the southern 

 shores — frequenting clayey mud, peat, and other media — often 

 in brackish water. 



A large species. Nereis longissima, Johnston, has a wide 

 di.'rtribution — ranging from Shetland to the southern shores 

 of England, and to a depth of 18G6 fathoms off the west 

 of Ireland (Ehlers, ' Porcupine,' 18G9), as well as in shallow 

 water in the Bay of Tunis in the ' Porcupine ' Expedition of 

 1870. The southern forms differ in tint from the northern, 

 as also does that from the Bay of Tunis. A more important 

 ])oint, however, is the occurrence of heterogomph bristles at 

 the inferior border of the upper series of bristles in the foot. 

 These, apparently, had hitherto been overlooked. 



