neio Species of Earthworms. 67 



Septa 7/8 aud 10/11 arc very thick and 11/12 only 

 slightly so. 



The oblique pharyngeal muscle-bands spring front the 

 posterior niartriu of somite 7 vcutrally, and pass inwards antl 

 forwards through septa 6/7 and 5/0 to l)c inserted into the 

 ventral pharyngeal pit. The dorsal muscles form a closer 

 matting structure, where the dorsal anterior wall of the 

 l)harynx is shot out, the whole i)harynx appears on dissection 

 a tubular structure, otherwise it is a spherical organ ocru- 

 l)yiiig somites 3-G. 



Tlie whole of the ventral wall of the pharynx is sacculated, 

 becoming a distinct pouch, iu somite 7. The gizzard is very 

 strongly developed ; it is a long tubular structure^ lying in 

 somites 7i, 8, 9^, and accordingly septa 7/8 aud 8/9 are 

 displaced by the length of half a somite. Well-developed 

 oesophageal pouches may occur iu somites 9 and 10, the 

 anterior being better developed. There is a typhlosole, 

 the intestine beginning in segment 14. No salivary glands. 



The last heart is m segment 11. A typhlosolar vessel and 

 a lateral longitudinal vessel are present, the latter occasion- 

 ally very feebly developed. 



The nephridia commence in segments 12-13. Those iu 

 13— IG are excessively large aud are brownish in aj)pearance. 

 Frequently the nephridia may have a similar colour iu one 

 or more lobes. Structurally also there is moditication. In 

 the anterior nephridia (13-16) the lobes comprise very large 

 oval cells, with deeply staining central nucleus. The proto- 

 plasm stains less easily. Clearing with glacial acetic acid 

 reveals nothing, except that the protoplasm of the cells 

 appears clearer and more granular. In sectional preparations, 

 (fig. 4, B & C) the ordinary nephridial cells appear de;^enerate 

 and block the system of draining-canals, the whole oigan thus 

 becoming a more solid structure with a rich plexus of blood- 

 capillaries. There is little doubt that the larger cells are 

 of secondary origin, though their source is doubtful. In 

 none of the teased or sectional preparations of these modified 

 nephridia could the occurrence of organic debris be fouud, 

 the entire structure looking under the microscope not 

 unlike that of an egg-sac. The exact nature of the function 

 fulfilled by these greatly modified nephridia is problematical. 

 The other nephridia iu the middle of the body have the 

 usual structure and disposition. 



3Iale organs. — Two pairs of testes and two large seminal 

 funnels in segments 9 and 10. The seminal vesicles, which 

 are four, are unequally developed, and in point of attach- 

 ment and position follow the usual rule (segments 9-12, the 



5* 



