MILAX GAGATES. 



141 



arises from the convex side of the epiphallus, and is fixed to tlie oviduct ; sperma- 

 THECA large and globose when fully distended, connected laterally to the oviduct by 



Fig. 160. 



Fig. 161. 



Fig. 162. 



Fig. 160. — Alimentary tract of Milax gagates, showing the buccal bulb and nerve-ring, X 2. 



Fig. 161. — Sexual organs of M, ^agates, X 3, the accessory glands turned aside to show the 

 protuberant atrium, alh.gl, albumen gland ; ot. ovotestis ; sp. spermatheca ; p.s, penis-sheath ; 

 ep. epiphallus ; r. retractor ; gl, accessory glands. 



Fig. 162.— Cephalic retractors of M. gagates, X 8. 



tissue and more firmly at the apex ; its short, stout stem opens into tlie free-oviduct, 

 at whose junction with the atrium are large foliated accessory glands with long 

 ducts, resembling salivary glands in their whiteness and lobular form. 



The CEPHALIC EETRACTOE, is somewhat variable in its development ; it usually 

 arises from the dorsum from a single root, and is often attached to, or beneath, 

 the apex of the shell, travelling a short distance as a single band; occasionally the 

 PHARYNGEAL and TENTACULAR portions may arise independently, each from its 

 own base or i-oot, but these are always closely contiguous; the pharyngeal muscle 

 is invariably deeply cleft, and the retractor of the right tentacle does not separate 

 the male and female organs, as in the typical 

 Limaces. 



Mandible or jaw moderately arcuate, thick, and 

 of a deepish horn colour, with very fine strife on the 

 anterior surface ; ends bluntly rounded ; median beak 

 or rostruin not prominent and very obtuse. 



The LINGUAL membrane is of the usual shape, and in a Christchurch specimen 

 displays series of closely-set teeth, projecting forward in the centre and sloping 

 backward towards the margins; the median series of teeth are slightly smaller than 

 the neighbouring laterals, and are distinctly tricuspid with the mesocone strong and 



Fig. 163.— Mandible or jaw of 

 Milax gagates, X 12. 



Fig. 164.— Representative denticles from a transverse row of the lingual teeth of A/, gagates, X 180. 

 The animal collected at Christchurch by Mr. C. Ashford, and the palate prepared by Mr. J. W. Neville. 



well developed ; the laterals are also clearly tricuspid, the mesocone gradually 

 increasing in strength and importance ; the marginals are chiefly bicuspid,, showing 

 a strong mesocone and distinct ectocone, the endocone so well developed on the 

 lateral teeth having become gradually lost, while the extreme marginals are simply 

 aculeate. 



The formula of a Christchurch specimen is 



ir + ^*- + J + TT + l-T X 98 = 7,938. 



Reproduction and Development. — The congress of this species may- 

 take place at any period of the year, during mild weather, and as is indi- 

 cated by the presence of a well-developed excitatory organ within the 



