OF SOUTHEEN INDIA. 17 



4. Teredo (Upehotes ?) glomerans, StoUczka, PL I, Kgs. 4-5. [/ 



T, (Tlperot.J tubnlis varie tortis, s(Bpe acglomeratis, Icevigatis, tenuibus^ termina- 

 tionibus anticis clausis, vix inflatis^ subtruncatis, Valvulis testes ignotis. 



This species is based upon two tubes found in a coarse, conglomeratic sandstone. 

 They are variously contorted, and one of them (of which a representation is given 

 in figure 4 on plate I) is extremely like some of the tubes of the recent Uperotes 

 clava, which generally bores in cocoanuts, or in floating pieces of wood. The tubes 

 are rather thin, smooth on the surface, with occasional projecting laminae on the turns 

 or bendings; they are sub-truncated anteriorly and closed, but not particularly 

 enlarged. No shell has been observed, nor any division or concameration at the 

 posterior end, such as often occurs in true Teredo or in Kuphus, 



Locality, — Oomarapolliam, in a greyish coarse sandstone. 



Formation, — Arrialoor group. 



b. Suh-family.—TEOLABINM. 



The animals of the tkoladinm resemble in general structure those of the 

 TJEREJDiNiN^, but they never grow^ to the same great length ; consequently the gills are 

 shorter in the former. The greater part of the body is covered with the shell, 

 formed by the two ordinary, or several other accessory, valves ; the mantle is cleft in 

 front to admit of protruding a small foot. The siphons are united nearly up 

 to the end, and do not, as a rule, secrete any palettes. A great peculiarity of most 

 of the PROLADiNM is the reflection of one part of the anterior adductor muscle 

 towards the beaks, often forming here a more or less cellular secretion, and in some 

 way replacing the ligament. This last is generally absent ; only in a few instances 

 rudiments of it were observed. 



The shell is, as I have already noticed, formed in all the Pholadidje on the same 

 principle. The valves generally are equal, inequilateral, with an internal apophysis 

 under the beaks, without hinge teeth, more or less gaping in front, and on the 

 surface with variously arranged imbrications which are sharpest on the front 

 part of the valves. An important character of a large number of the shells of 

 FROLADiN^ is the presence of the above-mentioned shelly reflection of the antero- 

 superior margin of the valves upon the beaks, covering these partially or totally. 

 A still more important distinction of this sub-family from the former is the presence 

 of accessory valves* in almost all frolabin^. The arrangement, form, and posi- 

 tion of these valves has been selected as the principal basis for generic distinctions 

 in the same manner as the palettes in the tjeeedininje. They are no doubt of great 

 importance, for their chief object appears to be to give the two large valves a certain 

 fixed position during the act of boring, when they could easily be dislodged ; but 



because these supplementary valves are in constant use their form is greatly variable, 



» 



^ Leacli introduced a special nomenclature for these valves as regards their position. They may be called umhonic, 

 pre- or post-umhonic, antero-superior, ante ro -inferior, anterior and posterior, ventral smd sipkonal ; the sigmficsLtioii 

 of these terms does not require any further explanation. 



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