CHAP. IV.] THE CRUISES OF THE ' PORCUPINE.' 189 



cone is continued beyond this by a number of 

 groups of needle-shaped spicules which surround a 

 narrow oscular opening. All parts of the sponge 

 are loaded with triple-toothed ' bihamate ' spicules 

 of the sarcode. 



On the 5th of August the ' Porcupine ' steamed into 

 Tangier Bay, after ineffectually trying to dredge in 

 190 fathoms off Cape Spartel. In Tangier Bay two 

 casts were taken at a depth of 35 fathoms. The 

 fauna was chiefly British, with a few more southern 

 forms. 



On the 6th of August Mr. Jeffreys went to Gib- 

 raltar, and there yielded up the reins to Dr. Car- 

 penter, going on to Sicily via Malta, for the purpose 

 of examining the newer tertiary formations in the 

 south of Italy, and the collections of fossil shells at 

 Catania, Messina, Palermo, and Naples, in connec- 

 tion with the results of his cruise. 



On Monday, the 15th of August, Captain Calver, 

 with Dr. Carpenter, who fortunately retained the 

 services of Mr. Lindahl as assistant, in charge of the 

 science department, steamed out into the middle of 

 the Strait for the purpose of commencing a series 

 of observations on the currents of the Strait of 

 Gibraltar. 



These experiments, which at the time were not 

 considered very satisfactory, were repeated and ex- 

 tended in the summer of 1871 by Captain Nares, 

 RTS"., and Dr. Carpenter, in H.M.S. 'Shearwater.' 

 Their curious results have been given in great detail 

 by Dr. Carpenter in the Proceedings of the Royal 

 Society of London, and by Captain Nares in a special 

 report to the Admiralty. As it is my purpose to 



