240 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.45. 



LIMA (ACESTA) CELEBENSIS, new species. 

 Plates 18 and 19. 



Shell large, oval, with the hinge shghtly curved, forming ahnost a 

 right angle with the long diameter of the shell, and scarcely at all pro- 

 duced anterior to the beak. Outer surface marked by many coarse 

 radiating ribs which are strongest on the lateral borders, particularly 

 on the very strongly excavated lunule. In the depressed grooves 

 between these ribs, finer threads frequently occur. Hinge broad. 

 Resilium deeply impressed, wedge shaped, as in Lima (Acesta) excavata. 



Two left valves and a lot of fragments probably belonging to these 

 two valves. Cat. No. 249133, U.S.N.M., were dredged at station 5647, 

 south of Korth Island, Buton Strait (lat. 5° 34' 00" S.; long. 122° 

 18' 15" E.), in 519 fathoms, on green mud bottom. One of these 

 measures; ait. 159 mm. 



A young specimen collected on the Philippine Expedition, Cat. No. 

 229395, U.S.N.M., without specific locality, undoubtedly belongs 

 here. I have given a figure of this also. 



LIMA (ACESTA) BUTONENSIS, new species. 

 Plate 20, figs. 3, 4. 



Shell small, irregularly oval. Hinge very slightly curved, extending 

 almost at a right angle to the long axis of the shell. Lunule excavated. 

 Outer surface marked by very fine, regular, and regularly spaced radi- 

 ating riblets which are a little stronger near the lunule than on the rest 

 of the surface and weakest on the middle of the disk. In addition to 

 the radiatmg sculpture, the surface is marked with fine concentric lines 

 which are emphasized in the form of resting stages at irregular inter- 

 vals. Ligament wedge shaped. Interior bluish white, edged with a 

 yellowish border. 



The single valve of this species, Cat. 239399, U.S.N.M., was dredged 



at station 5648, south of North Island, Buton Strait (lat. 5° 35' 00" 



S.; long. 122° 20' 00" E.), in 559 fathoms on green mud bottom. It 



measures: alt. 26.8 mm., lat. 22 mm.; diameter of single valve 5.5 



mm. 



EXPLANATION OF PLATES. 



All figures natural size. 

 Plate 12. Livia (Callolima) smithi, exterior. See page 236. 



13. Lima {Callolima) smithi, interior. See page 236. 



14. Lima (Callolima) philippinensis, exterior. See page 237. 



15. Lvnw (Callolima.) philippinensis, interior. See page 237. 



16. Lima (Callolima) rathbuni, exterior. See page 237. 



17. Lima (Callolima) rathbuni, interior. See page 237. 



18. Lima (Acesta) celebensis, exterior. See page 240. 



19. Lima (Acesta) celebensis, interior. See page 240. 



20. fig. 1. Lima (Callolima?) borneensis, exterior. See page 239. 



2. Lima (Callolima?) borneensis, interior. See page 239. 



3. Lima (Acesta) butonensis, exterior. See page 240. 



4. Lima (Acesta) butonensis, interior. See page 240. 



5. Lima (Acesta) verdensis, exterior. See page 239. 



6. LirrM (Acesta) verdensis, interior. See page 239. 



