130 Arenicolidae 



The examples from the Falkland Islands recorded by Miss Pratt 

 were abranchiate post-larval stages, and were referred to A. claparedii 

 because they possessed several oesophageal glands, a character which 

 was at that time known only in, and believed to be diagnostic 

 of, that species. The writer (1908) examined these specimens 

 subsequently and showed that they were A. assimilis vav. affinis. 



The specimen from New Zealand, recorded by Prof. Ehlers as 

 A. daiMredi Lev.,? is in the British Museum. Though it is not in 

 good condition its statocysts are demonstrable, and in its prostomiuin, 

 nephridia and crotchets it agrees with other examples of A. assimilis 

 var. affinis from New Zealand. 



Habits, Size, Colour. — The habits of this species seem to l)e 

 similar to those of A. marina. Dr. Michaelsen describes the 

 occurrence in the sand flats near Punta Arenas of the " Sand- oder 

 Pischer-wurm (Arenicola marina oder ein sehr naher Verwandter 

 dieses Nordsee-Thieres)," with its worm-like castings, of almost pure 

 sand, forming innumerable hillocks over wide stretches of the flats 

 uncovered at low tide. These observations relate to the typical 

 form of A. assimilis. 



The seven specimens of A. assimilis (typical form) examined by 

 the writer range in length from 110 to 160 mm. (the tail being 

 45 to 48 mm.). The examples of the variety affinis from the Falkland 

 Islands and the southern extremity of New Zealand are about the 

 same size as the foregoing. The largest examples are those from 

 Macquarie Island and Kerguclen, which are 217 and 208 mm. long 

 respectively (tail 85 and 38 mm. respectively), and the smallest are 

 those from Tasmania, which are 46 to 58 mm. long. 



Specimens, in alcohol or formalin, are brown, generally light 

 brown, and have a similar appearance to preserved light-coloured 

 examples of A. marina. A few have a rather darker tone, and some 

 are yellower, especially those obtained in Table Bay, which Prof. 

 Gilchrist states were of a striking yellow colour when alive. 



Variations in the Organs. — Examples of A. assimilis from 

 Fuegia, and of the variety from the Falkland Islands and from 

 Auckland Island, exhibit a tendency to the reduction or absence of 

 the first gill. None of the examples of the variety from Tasmania 

 has gills on the seventh segment, and only two (out of seven) have 

 gills on the eighth segment. The full number of gills is usually 

 present in specimens from other localities. 



