344 BULLETIN 100, UNITED STATES NATIONAL MUSEUM 



Biology. — The specimens from great depths resemble the others. 

 Those from Romblon and Mompog to the north of the Sulu Sea 

 resemble those from the Sulu Archipelago. There is a large avicu- 

 larium on specimens from all of the localities. This variety appears 

 to prefer the sandy and shelly bottoms. Our specimens were dead. 

 Geographic distribution. — Africa, on coral (Hincks). 

 Occurrence. — This is the most common variety in the region of the 

 Philippines. 



D. 5137. Jolo Light, Jolo; 6° 04' 25" N.j 120° 58' 30" E.; 20 



fathoms; S., Sh. 

 D. 5141. Jolo Light, Jolo; 6° 09° N.j 120° 58' E.; 29 fathoms; 



co. S. 

 D. 5145. Jolo Light, Jolo; 6° 04' 30" N.j 120° 59' 30" E.; 23 



fathoms; co. S., Sh. 

 D. 5147. Sulade Island, Sulu Archipelago; 5° 41' 40" N.j 120° 



47' 10" E.; 21 fathoms; co. S., Sh. 

 D. 5151. Sirun Island, Sulu Archipelago; 5° 24' 40" N.j 120° 



27' 15" E.; 24 fathoms; co. S., Sh. (common). 

 D. 5162. Tinagta Island, Tawi Tawi Group; 5° N.j 119° 47' 30" 



E.; 230 fathoms; S. brk., Sh. crs. 

 D. 5179. Romblon Light, Romblon; 12° 38' 15" N.j 122° 12' 



30" E., 37 fathoms; hard S.; 24.2° C. (common). 

 D. 5219. Mompog Island, between Marinduque and Luzon; 

 13° 21' N.; 122° 18' 45" E.; 530 fathoms; gn. M. 

 D. 5577. Mount Dromedario, Tawi Tawi; 5° 20' 36" N.j 119° 

 58' 51" E.; 240 fathoms; crs. S.j 12.4° C. 

 The fossils from the American Miocene and Pliocene belong to 

 this variety. However, the zooecia are arranged very much more 

 regularly and the large avicularia are never as expanded at the 

 extremity. 

 Plesiotypes — Oat. Nos. 8119-8124 U.S.N.M. 



SMITTINA TRISPINOSA var. ACUTA, new variety 



Plate 41, figs. 13, 14 



Description. — The peristomice is oval, the proximal border is very 

 concave. The lyrula is narrow and the two cardelles are small and 

 placed at the same height. A salient thread separates the zooecia. 

 The frontal is granular. The ovicell is globular and transverse 

 (0.25 mm. in diameter). On the frontal there is a small excentric 

 avicularium attached to the proximal border of the peristome; it is 

 very thin, little salient, and its beak is quite pointed. 



Measurements. — 



Peristomice! JP =(U0 mm " Zooecia!^ = :*™:* 5 mm ' 



\lp -0.09 mm. \lz -0.30-0.40 mm. 



This charming variety, rather regular in its general aspect, has 



been found only in a single locality. Our specimens were dead. 



