812 MR. G. E. DOBSON ON THE ANATOMY [June 21, 



Fig. 4. Bidiminus {Achatinelloides) hadihuensis, var. alba, p. 804. 

 6, 5 a. Btdiminus {Achatinelloides) balfouri, u. sp., p. 804. 



6. Bidiminus {Achatinelloides) figris, n. sp., p. 805. 



7. ( ) eehrimis, u. sp., p. 806. 



8. ( ) longiformis, n. sp., p. 806. 



9. ( ) semicastaneus, n. sjj., p. 807. 



10. ( ) , var. alba, p. 807. 



11. Enncsa iMssamaana, Petit, p. 808. 11 a and 11 b, views of basal portion, 



from right side and below. 



12. balfouri, n. sp., p. 809. 12« and 12i, right side of base, and aa 



seen from below vertically to columella. 



13. Ftiipa socofrana, n. sp., nat. size, p. 809. 



Plate LXIX. 



Fig. 1. Sfenogyra gollonsifensis, n. sp., nat. size, p. 809. 

 2,2 a. Stenogyra fumificata, n. sp., nat. size, p. 810. 



3. Stenogyra Jessica, n. sp., p. 810. 



4. adonensis, n. sp., p. 810. 4 a, right side of base. 



5. Stenogyra {Sttbulina?) enodis, n. sp., p. 811. 



6. (Opeas?) hirsiitus, n. sp., p. 811. 6 «, epidermal hairs, mag- 

 nified. 



7. la. Buliminus (Pachnodas) heliciformis, n. &]}., p. 807. 



8. Buliminus {Pachnodus) fragilis, n. sp., p. 808. 



9. ( ) adonensis, u. sp., p. 808. 9fl, the columellar margin, 



enlarged. 



10. Btdimiiius {Achatinelloides) gollonsirensis, n. sp., p. 805. 



11. Notes on the Muscular Anatomy of Cercopithecus 

 callitrichus. By G. E. Dobson, M.A., M.B., &c. 



[Eeceived April 5, 1881.] 



Having lately had occasion, while working at a question on general 

 comparative aiiatom}^ to dissect partially a fine male specimen of 

 Cercopithecus callitrichus* , I offer the following notes, then made, 

 to the Society for publication, as they contain some points of con- 

 siderable morphological interest. 



Anterior bellies of the digastrics greatly expanded and partially 

 double, occupying the whole intermandibular space, but united by 

 their fascial margins only, connected posteriorly by an aponeurotic 

 expansion with the body of the hyoid bone, the greater cornu of 

 which is also connected laterally by a tendinous band with the well- 

 developed intermediate tendon above, and behind by a small tendon 

 with the lower margin of the muscular fibres forming the posterior 

 part of the muscle, which are inserted obliquely into the intermediate 

 tendon, the infero-internal margin of which is seen to be directly 



* The following are the measurements of this specimen : — Length of head and 

 body (along back) 3' 7"-25 ; tail 2' l"-25; ear l"-2xl"; elbow to end of 

 middle finger 9'', knee to end of middle toe ll"-75, manus 3"-4, poUex l"-5 

 middle digit l"-5, pes 5"-3, hallux l"-2, middle digit 2". 



