340 TESTACEOUS MOLLUSCA. 



greater) propriety have been located in Mactra ; L. squamosa must 

 be set apart as belonging to the excellent genus 



LEPTON, Turton. 



" Shell fiat, nearly orbicular, equivalve, inequilateral, a little open 

 at the sides. Hinge of one valve with a single tooth and a transverse 

 linear lateral one each side ; of the other valve with a cavity in the 

 middle and a transverse deeply cloven lateral tooth each side, the seg- 

 ments of which divaricate from the beak. Ligament internal.' 1 '' 



L. squamosum (p. 28, as Lutraria s.), t. 9, f. 47. See, too, L.faba- 

 gella, Conrad (Am. Mar. C. 1. 11, f. 3), L. nitidum, Turton (Dith. Brit.) 

 and L. Clarkia (Brit. Mol.). 



On Mactea (p. 28). Consult the monographs by Spengler (Skriv. 

 Nat. vol. 5, pt. 2) and Reeve (Conch. Icon.). See, too, Zeit. Mai. 

 1848, 1849, 1850, 1851, Wieg. Arch. 1837, Proc. Bost. vol. 3, 

 Gould's Pacific Shells, and J. Conch, vols. 3, 4. 



On Mactra lactea (p. 31), striatula (p. 29) and ovaiina (p. 31). 

 The first (described and delineated from Poli) is only a variety of 

 M. subtruncata (p. 32) ; the second is not the species so named by 

 Linnaeus (Ipsa Lin.) and must consequently assume the earliest 

 correct published name M. alata (Spengler, Skr. Nat. Selsk. 1802); 

 the third, according to D'Orbignv, is identical with ill. fragilis of 

 Chemnitz {Ch.f. 235). 



Mactra maculosa, p. 29, t. 11, f. 27 ... M. fasciata, p. 30, t. 10, 

 f. 39 ... M. rufescens, p. 30, t. 10, f. 30 ... M. triangularis, p. 31, 

 t. 10, f. 40 ... M. lactea, p. 31, t. 10, f. 41 ... M. ovaiina, p. 31, 1. 10, 

 f.23 ... M. alba, p. 31, 1. 10, f. 27 ... M.squalida, p. 31, 1. 11, f. 30 ... 

 M. Brasiliana, p. 31, t. 10, f. 60 ... M. Lisor, p. 32, t. 11, f. 54, 55 

 ... M. truncata, p. 32, t. 9, f. I ... M. Australis, p. 32, 1. 10, f. 36 ... 

 M. elegans, p. 33, t. 11, f. 16 ... M. vitrea, p. 33, t. 10, f. 28 ... 

 M. exoleta, p. 33, t. 1 1, f. 51 ... M. elongata, p. 33, t. 10, f. 2 ... 

 M. Saidicc, p. 34, t. 13, f. 24 ... M. (I ?) nucleus, p. 34, t. 12, f. II 

 ... M. (MuliniaJ bicolor, p. 34, 1. 10, f. 3L ... M. ( MuliniaJ lateralis, 

 p. 34, t. 10, f. 25 ... M. (MuliniaJ Donaciformis, p. 34, t. 10, f. 29 ... 

 M. (MuliniaJ Byronensis, p. 35, t. 10, f. 38. 



Gnathodon cuneatus, p. 35, t. 10, f. 22. See, likewise, G. rostratus, 

 parvus, and tiigonus of Petit (J. Conch, vol. 4). 



Crassatella Kingicola, p. 35, t. 12, f. 17 ... C. Bonacina, p. 36, 

 t. 10, f. 58 ... C. sidcata, p. 36, t. 12, f. 22 ... C. rostrata, p. 36, 

 t. 9, f. 31 ... C. sid)radiata, p. 36, t. 9, f. 12, and t. 12, f. 14 ... 

 C. castanea, p. 36, t. 12, f. 23 ... C. decipiens, p. 36, t. 11, f. 9 ... 

 C.pulchra, p. 36, 1. 12, f. 18 ... C. lapidea, p. 36, 1. 10, f. 59 ... C.jubar, 

 p. 37, t. 12, f. 25 ... C. Corbuloides, p. 37, t. 12, f. 15 ... C.triquetra, 



