ANATOMY AND CLASSIFICATION OP THE ARENICOLID^. 431 



generally dark green in colour, but may be dark red or 

 occasionally yellowish red in colour. 



As we said above (p. 429), Arenicola Boeckii appears 

 to be merely a variety of A. ecaudata, and we are confirmed 

 in this opinion by the examination of a few specimens col- 

 lected by Mr. H. Hanna, of St. John's College, Cambridge, 

 and sent to us for identification by Dr. Harmer. The note 

 appended to them (written by Mr.Hanna) supplies some details 

 of their capture. " The specimens came from Murlougli 

 Bay, near Fair Head, co. Antrim. Four were found living 

 in deep circular pits, 2^ feet deep and about 1 foot broad, 

 in a raised bank of soft green sandstone near high water. 

 The bank of rock was washed over by waves at high tide. 

 The worms were of a bright scarlet colour, and lived in soft 

 greyish mud inside their membranous tubes, which slipped 

 off very readily." The form and position of the nephridia 

 show that these specimens belong to Arenicola ecaudata, 

 but as they differ in appearance from specimens of the usual 

 pigmented type in their transparent body-wall, and agree in 

 this respect and in size with Rathke's A. Boeckii, we con- 

 sider them to form a variety of the species A. ecaudata, 

 for which Rathke's name may be retained. 



Concerning the methods of oviposition and the habits of 

 the larva we have been unable to obtain any information, 

 but we have obtained three very young specimens of A. 

 ecaudata. 



On August 13th, 1896, while at Port Erin one of us col- 

 lected at a very low tide a large number of the "roots" of 

 Laminaria from the ruined breakwater, in the hope that 

 in their interstices some rare worms might be lodging. On 

 washing and examining the roots carefully one by one, many 

 worms were obtained, among whicli were three young speci- 

 mens of A. ecaudata. These are 7'2 mm., 8 mm., and 

 9'4 mm. long respectively. They are probably only a few 

 months old, and had but recently settled down to their 

 littoral habitat. They possess thirteen pairs of nephridia, 

 but no gills have yet been formed (PI. 24, figs. 35, 3G). 



