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Show 1877.] SOUTH-AMERICAN HELICIDAE. 365 conica, marginibus leviter convexiusculis, apice flavescente concolori ; anfr. 7, convexiusculi, lente accrescentes, sutura anguste pallida sejuncti ; apertura vix obliqua, ovalis, longitudinis totius testce £ paulo superans ; peristoma tenue, margine dextro bre-vissime (vix) expanso, columellari breviter dilatato et reflexo. Long. 21 mill., diam. 9 ; aperturse longit. 8i, diam. 5. Hab. Zaruma, South Ecuador. This pretty delicate species is easily recognized by its style of coloration. The transverse series of squarish spots, which are somewhat distant from each other, are very constant. They are not equally remote from one another, but sometimes three or four spots are quite close together and thus form a short almost continuous transverse band ; this is particularly the case with the two basal bands on the body-whorl. As the shell is so thin and semitransparent, all the markings are visible within the aperture. The two apical whorls under a strong lens are seen to be minutely granulated, as is the case in many other species. B. ziegleri of Pfeiffer, var. j3 ?, Mon. Hel. ii. p. 175 ; and B. maculatus, Lea (!=B. maculatus, Reeve), have similar styles of marking. BULIMUS (LIOSTRACUS) FUSCOBASIS. (Plate XXXIX. fig. 6.) Testa anguste perforata, elongato-conica, tenuis, semipellucida, nitida, alba, fasciis transversis plus minusve interruptis fuscis (in anfr. superioribus 2, in ultimo 3) ornata, ubique minute spiraliter striata ; anfractus 7-8, sensim accrescentes, convexiusculi, ultimus fascia infima haud interrupta ad basim sita; spira elongata, apice parum acuto nigricante; apertura leviter obliqua, intus alba fasciis pellucentibus, longit. totius J- adeequans; perist. tenue, vix expansum, margine columellari refiexo. Longit. 29 mill., diam. 12; apertura 11 longa, 6g lata. Hab. "Tarapoto, Andes of Peru, Mr. Spruce" (Mus. Cuming). This species was labelled in Cuming's collection as B. lividus, Reeve. On comparing the two specimens of it with the types of that species, I find certain characters which cannot be reconciled with Reeve's shell. The form and proportion of the whorls are different, also the length of the spire is greater in the present species, and its black apex and banding are good specific distinctions. The transverse bands in B. fuscobasis consist of elongate stripes only interrupted by white spaces generally shorter than the stripes, whilst in B. lividus the bands take more the form of quadrate spots widely separated. B. rectilinearis, Pfeiffer, is also allied to the present species; but it is more sharply conical, shows but the faintest traces of spiral striation, has not a black apex, is differently banded, and the columellar and umbilical characters are not similar. EXPLANATION Fig. 1 • Bulimus ochrocheilus, p. 362. 2. subpellucidus, p. 364. 3. flavidulus, p. 364. 4. albolabiatus, p. 363. 5. orthostoma, p. 364. I* PLATE XXXIX. Fig. 6. Bulimus fuscobasis, p. 365. 7. cequatorianus, p. 363. 8. roseolabrum, p. 362. 9 a, 9 b. Helix gealei, p. 361. |