dtf covered on the Coqfl of Pembrokeshire, &c. 



(>7 



Helix. Syft. Nat. 328. 

 iubulatus. 1. H. tribus anfrattibus longitudinaliter ftriatis. 



Obf. Singularis hac in fpecie eft conftructio, nam 

 tefta, umbilici loco, tubo marginato qui extra tefta? 

 fuperficiem extenditur, inftructa eft. Fig. 35, 36. 

 variegata. 2. H. tefta lasvi quatuor anfractibus, primo ventrico- 

 fiore, lineis rubris notatis. 



Obf. Bali imperforata. Tefta fubpellucida, aper- 

 ture margine patentiffima. 



Nerita. Syft. Nat. 329. 



pel/ucida. 1. N. tefta lam pellucida, anfractibus tribus. 

 alba, 2. N. tefta lasvi fubpellucida, duobus anfra&ibus. 



The following Marine Animal appears to conftitute a new genus 



among the Fermes Zoophyia. 



Derris. 

 Gener. Char. Corpus teres articulatum ; os terminale, tentacula 



duo. 

 fanguinea. D. — Tab. 13. f. 1, 2, 



Obfervaiions* 



THIS fingular animal is of a cylindrical form, gradually de- 

 creafing to the anus, and terminating in an acute point. It is com- 

 pofed of joints, and capable of the greateft flexibility : the body is com- 

 posed of an external membranaceous tranfparent coat, that furrounds 

 the internal parts ; which are rendered vifible by the pellucidnefs 

 of the covering. The head is extended beyond the outer fkin, and 



K 1 is 



