1^4 M. M. SCHEPMAN, LAND- AND FRESHWATER MOLLUSCA ETC. 



4. Melania (Stenomelania) lorentzi n. sp. PI. V, fig. 5. 



Shell subulately turreted, rather strong, colour under a thick, black crust, pale greenish- 

 olive, without any markings (as far as I can see by scratching off the crust). Spire in most 

 spécimens but slightly eroded, remaining whorls 7 — 9 (may be more or less in some spéci- 

 mens), scarcely convex, separated by a distinct suture. Sculpture consisting on the upper 

 whorls, which hâve an infrasutural groove, of a few, about 6 lirae and more or less numerous 

 ribs, which are very spacious on the lower whorls, where they hâve the character of varices ; 

 last four whorls nearly smooth, only with very fine growth-striae and one or two spirals 

 above the suture, last whorl elongated, with a few spirals at the base. Aperture elongate, 

 narrow above, but in quite developed spécimens not acute above, but with a sinus if seen in 

 front, rounded but slightly compressed at the base, peristome thin, with a sinus above, roundedly 

 protracted below, if seen from the side ; columella rather straight, body-whorl with a con- 

 spicuous layer of enamel. 



Alt. nearly 33, lat. ioV 4 ; apert. ait. 11".,, lat. 4 mill. 



New Guinea, creek near Bivak Island, May n, 1907 ; Lorentz River, May 7-8, 1907; Sept. 3-5, 1909. 



Most spécimens resemble M. papuensis Q. & G., as figured by Brot (Martini-Chemn., 

 Ed. II, Melania, PI. 21, fig. 10), but I can find no trace of the colourmarkings, on which 

 Brot lays much stress, that species has no ribs on upper whorls, the aperture is, according 

 to description, very différent, even if one considers that in the majority of the spécimens of 

 the new species, from the river, its upper corner is nearly acute, without distinct sinus. It 

 resembles also in part M. clavus Lam. (Brot, 1. c. fig. \ja) but in that species the peristome 

 is straight. 



The spécimens differ more or less in development of sculpture of upper whorls and at 

 the base, also in the shape of aperture, as mentioned above, but after comparing the numerous 

 spécimens, I think they belong without doubt to one and the same species. 



5. Melania (Melanoides) alkmaarensis n. sp. PL V, fig. 6. 



Shell turreted, rather strong, shining, brownish-olive, with brown spots, especially below 

 the sutures, and some more scattered spots and fiâmes on the rest of whorls, (covered with a 

 ferrugineous crust), spire nearly entire ; whorls 10, moderately convex, separated by a slightly 

 margined and especially in the lower whorls, deep and slightly canaliculate suture. Sculpture 

 consisting on the upper whorls of spirals, crossed by nearly equal, riblike striae, which in 

 the lower whorls, where the striae hâve the character of ribs, occupy only the lower part of 

 whorls, 4 in number and form fiât, spiral spaces, separated by impressed striae; the upper 

 part of thèse whorls is rather smooth, with only a few more or less obscure spiral lines ; 

 last whorl below periphery, with about 15 spirals, moreover many parts of the shell are 

 wrinkled. Aperture oval, its upper corner acute, peristome thin, its lower part protracted, 

 base narrowly rounded, columella slightly curved, interior of aperture bluish-white. 



Alt. 37, lat. 12; apert. ait. 12, lat. 6 mill. 



New Guinea. Alkmaar, July — Aug. 1907. 

 Allied to M. singularis Tapp. Canefri, but differing by sculpture, that species (Fauna 



