MARINE BIOLOGICAL STATION AT PORT ERIN. 113 



on the 16th chsetigerous segment, and of well-marked 

 notopodia on the first segment. The corresponding 

 neuropodia are not closely approximated in the mid-dorsal 

 line. 



" The third species of Arenicola found in the district 

 occurred along with A. ecaudata in fine gravel on the 

 south side of Bay-ny-Carrickey, and also, though not so 

 abundantly, on the south side of Port Erin bay. It 

 is certainly the A. grubii of Claparede, which has been 

 hitherto described from Naples, and agrees with his 

 description (incomplete though this is) in all essentials 

 as in the number and position of the gills, the number 

 (five pairs) and relations of the nephridia, and the form 

 of the chaetae. 



"In our specimens, the first pair of notopodia are 

 absent or extremely reduced, so as to be very rarely 

 visible externally, while the corresponding neuropodia 

 are continued upwards and inwards, so that they almost 

 meet in the median dorsal line. The first pair of gills is 

 attached to the 12th chastigerous segment. Of the five 

 pairs of nephridia, the first opens on the 5th segment (as 

 in A. ecaudata), and corresponds in position with the 2nd 

 nephridium of A . marina. In addition to these observa- 

 tions (which introduce A. grubii, hitherto only known 

 from the Mediterranean, into the British Fauna), some 

 further work was done upon the anatomy of A. marina, 

 and the result of this investigation will appear shortly in 

 the ' Quarterly Journal of Microscopical Science.' 



"Of these three species, A. marina contained little 

 or no traces of reproductive organs. Kipe females of 

 A. ecaudata and of A. grubii were abundant, though 

 males were scarce and immature (March 26th to April 

 16th, and the same appeared to hold good at Whitsuntide). 

 It appears that the shore lugs are ripe in the middle of 



