226 TELETHUSJS. 



Fam. XIII. TELETHUSiE. 



TBLETHUSiB, Savign. Syst. Annel. 70 & 95. Latr. Fam. Nat. 244. 

 Paromocrisea, Elainv. in Diet. cit. Ivii. 444. 

 Les Arenicoles, Cuv. Reg. Anim. iii. 197. 

 Arenicoliens, Aud. Sf M.-Edw. Litt. de la France, ii. 282. 

 ARENicoLiDiE, Johnston in Loud. Mag. Nat. Hist. viii. 566. 

 Telethusa, Grube, Fam. Annel. 74. 



Char. Body vermiform, cylindrical, more or less inflated anteriorly, 

 consisting of segments differently organized and formed of interme- 

 diate rings : head none ; the first segment with a terminal circular 

 mouth from which a short thick muricated proboscis is evolved: 

 branchiae arbuscular, attached at the base of the dorsal branch of 

 the feet of a certain number of segments, for there are none on the 

 anterior segments : feet similar, scarcely protuberant, biramous, the 

 dorsal branch with capillary bristles only, the ventral formed by a 

 series of crotchets. — Borers in sand. 



The worms which constitute this small family are of the number 

 of those which connect the Annelides errantes with the A. tubicolae, 

 their organization being of that undecided and commixed character 

 which leads some naturalists to place them in the former order, and 

 others, of equal authority, in the latter. Savigny, for example, 

 arranges the Telethusce among the SerpulidcE, a family of Tubico- 

 lans ; but Cuvier makes them members of his Dorsibranches, — an 

 order almost coequal with the Errantes of Audouin and Milne- 

 Edwards. 



The body of the TelethustB is vermiform, cylindrical, and formed 

 of comparatively few segments ; but the segments themselves are 

 annulated, or divided by a certain number of less decided circular 

 plaits or rings. It is acephalous and obtusely pointed in front, 

 truncate behind ; and, for the sake of description, may be divided 

 into three portions, — an anterior, which is generally inflated and 

 always without branchiae, — a middle, distinguished by carrying the 

 branchiae, — and a posterior, which is both apodous and abranchial. 

 This part is absent in one of our species. At the apex of the anterior 

 extremity we find the mouth, which is provided with a short thick 

 edentulous proboscis roughened with conical fleshy papillae : there 

 are neither eyes, nor antennae, nor cirri. The feet are all similar in 

 structure, and consist of a dorsal branch garnished with proper 

 bristles, and of a ventral ridge (scarcely perceptible on the anterior 

 segments), surmounted with a series of imbedded hooked bristles*. 

 The bristles are not smooth, but are feathered with spinules that are 

 directed upwards to the point of the bristle f. Upon a certain num- 



* Oersted, Ann. Dan. tab. 1. f. 13. 



t See a figure by Oersted in his Consp. Annul. Dan. pi. 1. f. 1, but the spinules 

 seem to be represented as mere denticles. Dr. Williams's figure is more correct. 



