174 TEREDIXID.E. 



rejecting altogether the time-honoured name navalis, 

 and applying it to the species now described. Da Costa 

 called it Serpula Teredo, Spengler T. batavus, Lamarck 

 T. vulgaris, and Van der Hoeven T. Sellii. 



3. T. pe'dicella'ta"^, Quatrefages. 



T. pedicellahis, Quatref. in Ann. Sc. ^'at. 3e ser. (Zool.) t. xi. p. 26, 

 pi. i. f. 2. 



Body not so long as that of T. lutvalis, and of a thinner 

 texture : tubes rather short, separated half way (Quatrefages). 



Shell scarcely distinguishable from that of T. Tmvalis. It is 

 alwaj's smaller ; the striae which cover the anterior area are 

 usually fewer, and consequently more remote, and the auricle 

 of the posterior area (especially in the young) is placed 

 somewhat higher up. The pallets however are unmistakeably 

 distinct. They are to a certain extent compound, and consist 

 of three separate portions. The stalk is very long and cylin- 

 drical : the blade or middle portion is roundish-oval, not much 

 raised, and flat below ; the upper part of the blade on each 

 side is dark brown or chocolate, and forms a strongly marked 

 band ; it is laminated on the under side : the third or outer 

 portion is square, and is often notched or bifurcated like the 

 outer part of the pallet-blade in T. mivalis, but never so 

 deeply nor excavated ; this third portion is sometimes ivory- 

 like, as well as the stalk and blade, and at other times yellow- 

 ish-brown, or of a horny substance. The sheath is thinner 

 and more decidedly jointed; and it is always shorter and 

 narrower than in T. navalis, showing that the animal 

 of the present species does not burrow so deeply. Valves, 

 L. 0.2, B. 0-2; pallets, L. 0-175, B. 0-05 ; sheath, L. 0-25, 

 B. 0-2. 



Yar. truncata. Corresponding with the varieties of the 

 preceding two species. 



Habitat : Fir and oak used in submarine and fixed 

 woodwork at Guernsey, Alderney, and Sark (Lukis). 

 It was originally discovered by Quatrefages in the Bay 



* From the long pallet-stalks. 



