146 CAMFORNIA ACADEMY OF SCIENCES. 



bed of tlie river ><outli of tijwii at a water-hole in the otherwise dry creek bottom 

 sand. It occurred here with Deltania and Liiniiodrihis. Tlie .sand was merely moist 

 on account of overlyinj^ rubbish and .sacks. The species is undoubtedly a native (jiie 

 and the only Acanthodrilid f(jun(i on the coa.st so far north in the open {ground, ami 

 and on this account even of geoti;ra|)hical interest, 'i'iie intestine of the worm was 

 gorj^ed with the coarse white .sanil of the river beil. The anterior part of the worm 

 was cut lengthwise, one-half dissected and the other half sectioned cro.sswise. The 

 want of specimens made a full investigation impossible, though I believe none of the 

 important points remains in doubt. 1 have no reason to believe the species is scarce, 

 though piohably it isshariiig the fate with all native worms, that of being displaced by 

 European importations. The species is dedicated to Professor W. .S. Keyes, my com- 

 panion in many travels in tropical Mexico. 



Ajfinities. It is interesting to note that Aleodrilus shows considerable affinity 

 to the only other North American genus of this family, viz.: Diplocardia. It re- 

 sembled this genus by having two gizzards, no calciferous glands, meganephridia, no 

 sacs with penial seta?. It resembles Eenhamia in having two gizzards, etc., but it 

 differs from these two, as well as from all other Acanthodrilid.c, by the far backward 

 position of the' prostate and spermiducal pores, these being in xx, xxi and xxii re- 

 spectively, while all other genera of this family have these respective pores in xvii, 

 xviii and xix. The genital male pores are thus in Aleodrilus pushed three somites 

 further back. Considering these and some minor characters I believe I am justified 

 in ])lacing this worm in a new genus. 



Aleodrilus Keyesi n. sp. 



Definition. Leiu/th 7 cm., by fi mm. wide; number of somites SO. First dor- 

 sal pore vlii-ir. Clitellum complete in (interior, incomplete in the posterior somites, 

 ^xiii-h^v. iVb penial sacs and setce. Common setre paired, those of the inner couple 

 closer than those of the outer couple. Spermathecal pores between vii/viii and viii/ix. 

 Gizzards in v and vi. No calciferous glands. Nephridia nut covered by a celotnic man- 

 tle. Nephrop)orcs outside of seUv 4. Hearts in x, xi, xH. jSperm-sacs racemose in x, 

 xi, xli. Testes in x, xi. Color pale flesh, no pigment. Habitat, Northern Baja Cal- 

 ifornia, at Ensenada de 2'odos Santos. 



EXTERNAL CHARACTERS. 



Color is very pale, mottled and marbled, showing clearly the intestines and 

 blood vessels. When collected this worm resembled in delicacy of color and trans- 

 parency Deltania eleyans and I supposed it to be this species. Spermathecal pores are 

 separate in front of setic 1 and 2 between vii/viii and viii/ix. Setd are ventral and 

 lateral, H in each somite ap[)roached in couples. The setic of the inner couple is 

 closer than those of the outer couple. The tlistance between the couples is about twice 

 as large as the distance between sette 1 and 2, and one antl one-half as wide as the dis- 

 tance between seta? '■'> iin<l I. No penial seta' in special sacs. All seta' an- sigmoid 

 without sculpture. The anterior live somites are two-ringed, that is with a single 

 groove in the equatorial i-cgion, while all the tollowing somites are four-ringed, or 



