P. TESTUDINARIA. _P._ ovata glaberrima integerrima. P. RUSTICA. _P._ integra, striis 50 obtusiusculis. P. FUSCA. _P._ ovata integerrima, striis elevatis, vertice obtuso. The intended name was _cinereo-nigricans_. P. CRUCIATA. _P._ ovalis convexa integerrima, cruce picta. P. RETICULATA. _P._ conica compressa, superficie reticulata. The suggestion I have elsewhere made that this uncertain shell might prove the European _Pedicularia_, induces me to remark that, although _P. Sicula_ has been supposed to be a comparatively modern discovery, Favanne had long ago delineated it in the fourth plate (f. H. 1.) of his enlarged edition of d'Argenville. P. NIMBOSA. _P._ conica ovalis, costis confertis, vertice perforato. The discrepancy between the heading borrowed from the 'Systema', and the after details, is removed by the substitution of the original one. The shell was termed _perforata_ (not _nimbosa_), and was wrongly identified by Linnæus with the striated brown _Fissurella_ of the 'Systema'. * * * * * In addition to the printed species, the two following were present in the manuscript copy. P. SOLARIS. _P._ ovata integerrima, striis subnodosis, vertice acutiusculo. Testa ovata, diaphana, magnitudine extimi articuli digiti, margine integerrimo, lævis, striis subtilissimis inæqualibus numerosissimis, fasciis longitudinalibus rubris albo passim maculatis. Mucro acutiusculus obliquus albidus. This was placed in the section having a simple margin. P. PERFOLIATA. _P._ conica, reclinata, perfoliata. Testa magnitudine coryli nucis, conica, sed cono retro inclinato, acutissima, alba, imbricata lamellis horizontaliter testam cingentibus. Margo integer, ovalis, antrorsum gibbus s. dilatatus. Cavitas profunde glabra. This description very fairly suits the _Patella antiquata_ of the twelfth edition of the 'Systema'. DENTALIUM. Testa univalvis, subcylindrica, utrinque aperta. Spira regularis nulla. Although the _Serpulæ_ were intermingled, it is clear that they did not accord with the above definition. D. ELEPHANTINUM. _D._ subulatum subarcuatum, angulatum. The synonymy of the tenth edition was appended, Lister excepted; the erroneous 13 of the reference to the Gazophylaceum was erased. _Dens elephantis_ was the proposed trivial name. D. ENTALIS. _D._ subulato-cylindricum, subarcuatum. The terminal details were not furnished. _D. dentalium_ was the intended appellation. SERPULA. In the original version of the 'Museum Ulricæ,' the members of this genus are not separated from the _Dentalia_ (a proof, among many others, of the early date of this catalogue). Linnæus, however, when revising the transcript, had meditated the withdrawing of _S. arenaria_ and _lumbricalis_, and constituted for them a nameless genus with the following definition:-- Testa tubulosa, isthmis concamerata, dissepimentis integris, nec perforatis, s. communicantibus. This genus would have been the equivalent of the modern _Vermetus_.