Thus it is used of the purchase used in raising the flukes of an anchor to the bill-board; of a piece of wood or metal used to strengthen a sprung mast or yard; and of a plate of metal used, as in railway construction, for the strengthening of the meeting-place of two rails.
English Channel being: length from nose to notch between the flukes of the tail, 622 in.; from the nose to the front edge of the dorsal fin, 29 in.; height of dorsal fin, 42 in.; length of base of dorsal fin, 8 in.; length of pectoral fin, 94 in.; breadth of pectoral fin, 32 in.; breadth of tail flukes, 13 in.
It has been compared with the canal of Laurer of Trematodes (the vitello-intestinal duct of the ectoparasitic flukes), but if we take the more primitive Cestodes, and especially Aniphilina, into consideration we find that they possess, in addition to the uterus, an anterior vagina (usually present in Cestodes) and a posterior one.