Miscellaneous. 431 



setarum capillarium non exsertilium includente et duabus ventralibus 

 absque setis. 



Segmentum duodecimum et omnia sequentia (quorum numerus 

 fere 130-140) subteretia, anteriora longa sensimque posterius bre- 

 viora, pinna dorsali conica vel subcylindrica apice globoso et fascicule 

 setarum capillarium instructa, ventrali duplici ut in segmento lOmo 

 et 11 mo, et absque setis. 



Animal in tubo iuclusum erecto, longissimo, cylindrico, pergamen- 

 taceo, tenuissime transverse sulcato seu annulato, extremitate inferiore 

 affixo. 



Spiochcetopterus typicus, Sars. Unica species (pp. 7-8). 



The remarkable genus Chcetopterus, Cuvier, has hitherto occupied 

 an isolated position amongst the other Annelides. Audouin and 

 Milne-Edwards in 1833 established it as a distinct family {CJice- 

 tojjterea), and their example has been followed by all subsequent 

 authors. But there has always been a doubt as to its true place in 

 the system and its affinities with other Annelides. The above-men- 

 tioned French zoologists even thought that it would be most natural 

 to form a distinct order for this animal, but they placed it, evidently 

 incorrectly, hetvfeen Penj)afi(s and Arenicola. Grube (in 1850) was 

 not more fortunate in placing it between Siphonostomum and ylreni- 

 cola. Lasth', R. Leuckart (in 1849) was the only person who 

 prognosticated the family to which the genus Chcetopterus should 

 belong, namely the Ariciea. 



This new animal forms a remarkable connexion between ChcB- 

 topterus and Spio. It has only been taken at Helle, in the neigh- 

 bourhood of Manger, near Bergen, in mud at a depth of 40-50 

 fathoms in company with Virgularia ^yiirabilis, Midi. — Fauna litto- 

 ralis Norvegice, Second part, 1856, pp. 1-8. 



On the Sea Sawdust of the Pacific. By John Denis Macdonald, 

 Esq., Assistant Surgeon R.N. 



The Author gives a description of the remarkable little Alga so 

 frequently met with in the South Pacific, scattered over the surface 

 of the water in broad streaks and patches of a pale yellowish-brown 

 tint, and which is known under the name of " Sea Saw-dust." 



After adverting to the occurrence of a similar pheenomenon in other 

 parts of the globe, and citing the account given of the Trichodesmhan 

 erg ihrceum of the Red Sea by MM. Evernor Dupont and Montagne, 

 together with a description extracted from the ' Colombo Herald ' 

 of May 14, 1844, of what was obviously an example of a vegetable 

 scum of the same kind occurring on the sea off Ceylon, the author 

 remarks, that in the instances met with by himself he did not re- 

 cognize the fffitid odour so generally and pointedly spoken of in the 

 accounts of others. He then states the results of his own observation 

 as follows : — 



" It was rather difficult at first to determine whether our species is 

 to be referred to the Oscillatoridse or the Confervidse. In the latter, 



