20 DESCRIPTION OK A NKW FI.AMMUMNA FROM NEW ZEALAND. 



the only imperforate species of the sub-genus Tlialas><uheJi.c I kiiow. The 

 animal is of a yellowish brown colour, with a black band and spots on the 

 mantle, distinctly visible through the shell on its periphery. The caudal 

 pore (Fig. 4) is very distinct in this species, and is surrounded by a number 

 of roundish papillae. The jaw (F'ig. 5) is arcuate, thin and fragile, com- 

 posed of exceedingly fine vertical lamellae. The radula (Fig. 6) is tongue- 

 shaped, composed of many, about 100, transverse rows of teeth which have 

 the formula 28 — 7 — i — 7 — I'S. The ihachidian tooth has a mesocone ex- 

 tending a little i)eyond the base, and two minute ectocones. The lateral 

 teeth are very similar to the rhachidian ; the transition teeth show the 

 entocone and mesocone fused together into one, a small ectocone being 

 left. The marginals have apparently only the mesocone left, and there is 

 on most teeth a minute ectocone present, which sometimes is split up into 

 two. This dentition is that characteristic of the sub-genus ThaIas.fohelix, 

 in which, however, the ectocones of the rhachidian tooth are mostly obsolete 

 and the marginals with a mesocone only. 



The digestive and reproductive organs (Figs. 7 — 8) are those we usually 

 find in Flainmulina, Endodtmta and Laoma. 'I'he salivary glands are fused 

 together and the stomach is rather large. The vas deferens enters the 

 distal end of the penis sac exactly at the place where the retractor muscle 

 is affixed ; the penis is covered with rugosities of irregular shape. 



Reference Letters. 



h.c. Buccal mass. r.s. Keccptaculiim seniinis. 



<•/;. i^l. Digestive gland. .s.(/. Salivary duct. 



iut. Intestine. s. ,4;/. Salivary gland. 



/>. Penis. st. Stomach. 



r. Rectum. v.d. Vas deferens. 



r.ni. Retractor muscle. 



EXPLANATION OF PL.ATE V. 



Figs. I, 3, Shell of Flaiiiiniiliiia Iciiiii^/, n. sp. 



Fig. 4. Caudal pore, magnified. 



'"'to- 5- J^w, greatly magnified. 



V\g. 6. Teeth of Radula, x 240. 



Fig. 7. Digestive organs, magnified. 



Fig. <S. Reproductive organs (part only), magnified. 



