FROM THE EDDYSTONE GROUNDS TO START POINT. 509 



sufficiently strong to upset it. On examining a specimen of Aporrhais 2}es-pelecani it will 

 be seen that, when on its back, it lies indilferently on either side of a line drawn between 

 two points, of which the end of the middle wing-like process is one, and one of the 

 nodules on the body-whorl the other. The shell will rock freely backwards and forwards 

 across this line ; and experiment jn'oves that a very moderate alternate current will suffice 

 to replace the shell in its normal position. I have tried this experiment over and over 

 again, not only with Aporrhais, but also with heavy foreign shells furnished with spines, 

 processes, and more or less developed lips, such as Mure.r, Pteroceras, and Slrovibus. In 

 many cases the righting action of wave currents is most marked." 



Eidima jJolita. Living specimens of Eulima polita were obtained 

 twice, once in haul 84, on the coarse gravel mixed with fine sand of 

 Ground XI., and once in haul 103, on Ground XIII., where the bottom- 

 deposit is coarse gravel mixed with' mud. 



Distribution. Geographical. Finmark to j^gean (Jeffreys). 



Depth. 2-80 fathoms (Jeflreys). 



Bottom-deposit. Forbes and Hauley state that Eulima polita frequents sandy bottoms. 

 Forbes (Brit. Assoc, 1850) gives seven records from coarse ground (shell, nullipore, gi-avel, 

 etc.) and two from sand. Gwyn Jeffreys says it is found on muddy sand. Metzger 

 (No. 77) records it once on stony ground. 



Natica nitida { = N. Alderi of Jeffreys). One specimen only in 

 haul 46, on Ground XI., bottom coarse gravel with fine sand. 



Distribution. Geographical. Lofoten Islands to Mediterranean (Jeffreys, No. 55). 



Depth. Low-water to 135 fathoms (Locard, No. 69). 



Bottom-deposit. Forbes (No. 24, Brit. Assoc, 1850) gives thirteen records from coarse 

 ground, five from sand, three from nuid. Gwyn Jeffreys says it occurs everywhere in sand. 

 Metzger (No. 77) gives eleven records on coarse ground, twelve on sand, line sand, or 

 sandy mud. It appears, therefore, that the species frequents coarse and fine ground about 

 equally. 



Zamellcma perspicita. A few specimens of this species were obtained 

 on Grounds VII. and XL in the neighbourhood of the Eddystone and 

 on the Bolt Head shell gravel (XVIL). It is generally found crawling 

 on hydroids. 



Distribution. Geographical. Norway to Azores, Madeira, and Mediterranean. Also 

 Canadian and United States Atlantic Coasts (Jeffreys). 



Depth. Low-water to 704 fathoms (Dauzenberg, No. 20). 



Bottom-deposit. Most abundant on sea-weeds, etc., in tidal and laminarian zones. 



Nassa incrassata. This was taken alive on the Prawle Stony Ground 

 (XVIIL). 



Distribution, Geographical, Iceland to Azores and Mediterranean (Jeffreys). 

 Depth. Low-water to 145 fathoms. 



Bottom-deposit. The authors agree that the species frequents stony gi'ound, especially 

 in the tidal and laminarian zones. 



Buccinum undatum (Chart XV.). The common whelk was numerous 

 on the gravel and coarser sand grounds in the neighbourhood of the 

 Eddystone and on the Bolt Head Shell Gravel. It was entirely absent 

 from the fine sand of the outer and inner trawling grounds, and was 

 only taken once on the Prawle Stony Ground (haul 45). 



As will be seen from Chart XV., the species was absent also from the 

 clean shell gravel clo.so to the Eddystone rocks (Ground XVI.), and was 



NEW series.— vol. V. NO. 4. 2 L 



