(26) 



DESCRIPTION OF THE FIGUEES OF ARENICOLA 

 LOVENI KINBEEG. 



PLATE I.* 



FIG. 



1. The prostomium of the type specimen. Dorsal aspect. N.GR. Nuchal groove. 



x 10. For description, see p. 5. 



2. The posterior end of the body and the first three tail segments of the type 



specimen, seen from the right side, showing : A portion of the nineteenth 

 segment, namely, the nineteenth chsetigerous annulus, with its neuro- 

 podium (NR.'9), notopodium (N. 19 ), and gill (En. 13 ), and the following 

 ring; the extra, twentieth, segment and notopodium (N. 20 ) which this 

 specimen possesses; the pit (P.), possibly sensory. The ventral axis 

 of the gill (BE. J 3) is represented, but only the origins of the other axes 

 are shown, x 5. For further description, see pp. 6, 7. 



3. Distal third of one of the shorter notopodial setae from a Saldanha specimen, 



showing the " teeth," the transverse striation, and the lamina, x 90. 

 A portion, from the part marked +, is seen highly magnified in Fig. 4. 



4. A portion of a notopodal seta, showing the toothed crests or " Sageblatter." 



X 1000. For descriptions of Figs. 3 and 4, see pp. 8, 9. 



5. The anterior portion of the type specimen, as far back as the sixth chastigerous 



segment, opened by an incision along the mid-dorsal line. The figure, 

 which is natural size, shows : The pharynx (PH.) protruded, the pro- 

 stomium (PR.) and its retractor muscles, the three septa (S 1 , S 2 , S 3 ). The 

 first septum is pulled backwards, it is pierced by some of the retractors 

 (Pn.R.) of the pharynx, and bears the two enormous, muscular, septal 

 pouches (S.P.). The second septum is perforated by two apertures one 

 right and one left of the oesophagus to permit the passage of the septal 

 pouches. Close behind the third septum are the cesophageal glands 

 (CE.GL.) and the two hearts (H.), which are dilated, the right one fully. 

 The first (Npn 1 .) and second pairs of nephridia are shown. D.V. Dorsal 

 blood vessel. M OB. Oblique muscle band. N 1 . Setae of first notopodium. 

 N 3 . Setal sac of third notopodium, with its protactor muscles. ST. 

 Stomach. For further description, see pp. 12-14. 



6. Section of a statocyst of a Saldanha specimen (see p. 15). The epithelium, 



which forms the wall of the vesicle, is not well preserved, but several 

 sense cells (S.C.) may be recognised in it. Note also the single large 

 statolith and the strand (Nv.) of nerve and connective tissue continuous 

 with the sheath of similar nature which envelops the vesicle, x 110. 



* The cost of the original drawings for this Plate, and a portion of the other 

 expenses connected with the preparation of the report, have been defrayed by a 

 grant from the Earl of Moray Endowment of the University of Edinburgh. 



