HERRING FOOD 263 



[Boreopliausia], G. 0. Sars, 1883, has the basal joint of 

 the first antennse without an apical leaflet. It was esta- 

 blished to receive two northern species, which had been 

 successively placed in the genera Thysanopoda and Eu- 

 phausia, and which are now Boreophausia inermis (Kroyer) 

 and Boreophausia liascMi (Michael Sars). Both are found 

 in Scottish waters, and since Norman identifies Boreophau- 

 sia Baschii with RJioda Jardineana, G. Sim, 1872, it seems 

 that the generic name ought to be Rhoda. 



Thysiinopoda, Milne-Edwards, 1830, has only the last 

 pair of legs rudimentary, and even these have a well- 

 developed exopod ; the last pair but one are like those 

 that precede them. All the true branchiae are provided 

 with an anteriorly bent branch. The type species is 

 Thysanopoda tricuspida, Milne-Edwards. The British 

 species Thysanopoda Oouchii, Bell, and various others have 

 been transferred to different genera. 



Nyctiphdnes, G. 0. Sars, 1883, which means 'one that 

 shines by night,' like Thysanopoda, has only the last pair 

 of legs rudimentary, but the preceding pair are a little 

 imperfect, being devoid of the three terminal joints. In 

 both pairs the exopod is developed in the male, but want- " 

 ing in the female. The basal joint of the first antennae 

 carries a peculiar reflexed leaflet at the apex. Nyctiphanes 

 norvegica (Michael Sars) is reported from the Firth of 

 Clyde as abundant and fine everywhere in deep water, on 

 a muddy bottom, as far up as Loch Goil. Young speci- 

 mens are said to be not uncommon at the surface in the 

 Firth of Forth, especially in winter and spring. In certain 

 districts it forms an important part of the food of the 

 herrings. A specimen has been taken alive on the shore at 

 low water in North Devon. Nyctiphanes Couchii (Bell) is 

 distinguished from the preceding species by having no 

 lateral spines on the carapace and by having a spine over 

 the base of the telson. It is recorded from Cornwall and 

 Banff. Very like it is Nyctiphanes australis, Sars, which 

 appears to be restricted to the Australian seas. In de- 

 scribing this species Sars says that two of the female 

 specimens were ovigerous, a condition seldom met with 



