I have attached a mark of doubt to all the synonyms quoted above, 1st. on account of the difference of locality between Drury's Insect, and that described by Fabricius, which is from New Holland. 2ndly. Because Drury's description does not agree with the true Rh. mystacina: and 3dly. because as there is another spotted species of the genus found in North America, described by Laporte, it is most probable that Drury's insect is altogether distinct, in which case I have proposed for it the name of Rhipicera Druræi. Mr. Kirby speaks of the New Holland species of this genus as though there were more than one, and he has described one from that country under the name of R. femorata, in the 12th volume of the Linn. Trans. No. 9. in which the thorax, as well as the elytra, is spotted with white, whereas the thorax of Mystacina is described by Fabricius as being "cinereus." The Rh. mystacina of Laporte entirely agrees with Mr. Kirby's Rh. femorata. The Rh. femorata of Dalman is a totally distinct species from Brazil, and as it is necessary that a new specific name should be given to it, I would suggest that it should be termed Rh. Dalmanni. SAPERDA SPECTABILIS. Plate XLVIII. fig. 8. ORDER: Coleoptera. SECTION: Longicornes. FAMILY: Lamiidæ. GENUS. SAPERDA, _Fabr._ Cerambyx P., _Drury_. (SUBGENUS: ----?) SAPERDA SPECTABILIS. Nigra, thorace flavo punctis tribus nigris, elytris fasciis duabus flavis, apice truncato et spinoso. (Long. Corp. 9 lin.) SYN. Cerambyx spectabilis, _Drury_, _App. vol._ 2. _Sch. Syn. Ins._ 3. 421. (Saperda s.) HABITAT: Bay of Honduras. {75}Head black, with a large yellowish spot between the eyes. Antennæ black, and almost the length of the insect, having a row of short hairs running along the under side. Thorax black beneath, lemon-coloured above, with three black spots. Scutellum small, triangular, and black. Elytra black, with two broad straw-coloured bars crossing them, each having a spine at the extremity near the suture. Beneath black, except the middle of the abdominal rings, which is grey. PLATE XLIX. [Illustration] PRONUS (TITANUS) GIGANTEUS. Plate XLIX. fig. 1. ORDER: Coleoptera. SECTION: Longicornes. FAMILY: Prionidæ. GENUS. PRIONUS, _Geoffroy_. Cerambyx P., _Linn._ (SUBGENUS: Titanus, _Serv. Ann. Soc. Ent. France_, 1. _p._ 133.) PRIONUS (TITANUS) GIGANTEUS. Thorace utrinque bidentato, corpore nigro, elytris ferrugineis, antennis brevibus. (Long. Corp. 6 unc. 9 lin.) SYN. Cerambyx Giganteus, _Linn. Mant._ 1. 531. _Shaw Nat. Misc._ _t._ 280. _Fabr. Syst. El._ 2. 261. 17. (Prionus g.) _Oliv. Ent._ 4. 66. _p._ 12. _t._ 6. _f._ 21. HABITAT: Cayenne.