ON A SLUG OF THE GENUS YEKONICELLA FROM TAHITI. 



By T. D. A. COCKERELL, 



Entomoloijld, College of Agriculture and Mechanic Arts, New Mexico. 



Durino- the expedition of the U. S. Fish Commission steamer .1?J«- 

 tro.s.s to the South Seas, under the direction of Dr. Alexander Agas- 

 siz, collections were made on shore at various points and a few land 

 moUusks were o])tained. Among these was a specimen belonging to 

 the genus J^ronwdla, naked slugs which are common to many warm 

 countries and often very injurious to gardens. Being nocturnal m 

 their habits and capal)le of extreme elongation, so that they can pass 

 through verv narrow chinks, they have been known to destroy an 

 entire^crop of earlv tomatoes on one of the Florida Keys without being 

 detected until search was made at night with lanterns. During the 

 hours of daylight they retreated to the interstices of the coral rock 

 where in this case, although existing in immense luuiibers, they 

 remained invisible. The present specimen was submitted to the author 

 of this paper, who has made a special study of these animals, in order 

 that the species might 1)e determined and any facts of interest in regard 

 to it be placed on record. 



VERONICELLA AGASSIZl, new species. 



Tf^j,,>^^^o. 161956, U.S.N.M. 



Z>m'/v>^V>/^— Length, a])out 21 nun.; ])readth, 'Ji; breadth of sole, 3; 

 female orifice from sole, 2, from margin, si-arcely 2, from anterior end 

 about 11 nnn; these measurements all from a dried individual. Dorsal 

 surtuce granular with small warts; color, cotfee-brown marbled with 

 black; no dorsal })and. Under surface whitish. Anatomy not deter- 

 minable from the material available. 



JIahffo t.-Tixhiti; Tipaerui Valley, under bark of dead trees, col- 

 lected by Dr. Alexander Agassiz. {Alhxfr^m expedition.) 



Apparentlv nearest to V. (/ihoni Collinge, from the Fiji Islands, but 

 the sole is ])roader {cigaxsh! 8, gUson! 2.5 mm.) and the female gener- 

 ative orifice appears to be more distant from the sole. In size and 

 color the animal agrees fairly well with gasonl; at least, the difference 

 of color might be due to variation. From V. Irxnned Collinge, of the 

 New Hebrides, our animal difiVrs in the position of the female gener- 

 ati\e orifice. T" jAehyni Fischer, from New^ Caledonia, may also be 



compared. 



Proceedings U. S. National Museum, Voi XXIII-No. 1238. 



