Bartsch — A New Classification of the Shipworms. 29 



of the pallettes beyond these. The base of the siphons and the base of the 

 pallettes are surrounded by a membrane that forms a cupHke structure. 

 The siphons extend about the length of the pallettes beyond the termina- 

 tion of the pallettes and are separated throughout the distance that extends 

 beyond the pallettes. 



The type, Cat. No. 341,132, U. S. N. M., was taken by the author from 

 pilings in Pearl Harbor, Oahu, Hawaiian Is. It measures: height, 9 mm., 

 length, 8.5 mm.; thickness, 9 mm. The pallettes measure: length, 6 mm., 

 of which 2.5 mm. go to the blade, which has a diameter of 2 mm. 



I take great pleasure in naming this shipworm for Admiral C. W. Parks, 

 Chief of the Bureau of Yards and Docks, to whom I am indebted for much 

 help in connection with shipworm problems. 



Teredo (Teredo) beachi, new species. 



Shell subglobular, with a strong posterior auricle. Exterior milk white, 

 excepting the umbones and a streak in the median middle portion, which are 

 rose colored ; interior bluish white. The anterior portion forms a deep sinus 

 which is bordered by a narrow smooth edge, the external margin of which 

 is reflected over the anterior portion as a smooth callus, which is translucent 

 and permits the dental ridges covered by it to be seen through it. The 

 dental ridges radiate from this anterior smooth portion fanshaped backward 

 over the rest of the anterior area. There are about thirty-five of these in 

 the type, although some of the earlier ones may have been lost through the 

 erosion of the umbones. The dental ridges, which are finely denticulated 

 at their free margin, are about one-third as wide as the flattened spaces that 

 separate them at the junction of the anterior with the median portion. The 

 flattened interspaces are finely striated, the striations coinciding with the 

 dental ridges. The dental ridges of the anterior portion meet those of the 

 posterior median portion at almost right angles. The dental ridges of the 

 posterior median portion are closely crowded, being separated by a mere 

 line only. They are very strongly denticulated. The middle median por- 

 tion is a somewhat depressed area, which extends from the umbone to the 

 ventral margin. There is a strongly impressed line marking the center of 

 this area, which is crossed by rather rough, curved incremental lines which 

 extend equally rough over the posterior median portion. The posterior 

 portion forms a strong auricle, which is marked by rough lines of growth. 

 The interior has the umbones strongly curved inward, forming a prominent 

 knob, from the inside of which a strong, broad, thin blade extends, which 

 maintains almost an equidistance from the inside of the shell throughout 

 its entire length, the broad side of the blade being placed obliquely to this. 

 The junction of the anterior and median portion is marked by a slightly 

 thickened ridge on the inside. The center of the median portion is marked 

 by a roughened area which extends from the umbones to the ventral margin, 

 where the usual strong knob is present. The auricle extends over the pos- 

 terior median portion and forms a narrow, thin, free shelf, with very little 

 of a cavity behind it. The auricle is marked by strong, curved lines of 

 growth. The pallettes are spatulate, very short stalked and very broad, 



