BY W. L. MAY AND W. G. TOKK, LL.D., ETC. 



37 



POSTERIOR VALVE.-Mucro-post median dorsal area 

 striated as on median valves. The exposed portion is 

 almost circular and the surface is covered with elongated 

 pustules as in the other valves. Two slits. 



MEDIAE VALVES.-Dorsal area V-shaped, beaked, 

 longitudinally striated. Latero-pleural area covered 

 with irregular elongated tear-like pustules, becoming elon- 

 gated towards the eaves. A slightly-raised cost^ extends 

 trom the apex, and divides the latero-pleural area in two 

 sections, making the lateral area much smaller than the 

 pleural. Teeth 1—1, corresponding with ribs. Sinus 

 shallow and broad. Sutural plate vorj deep. Oreenish 

 colour inside. ' v^*ccuihu 



GIRDLE.-A spongy mass, densely clothed with needle- 

 iiive spicules. The pores are conspicuous with bundles 

 ot green spicules lying in the sutures. 



MEASUREMENT.. -Length 33, breadth 12 mm 

 ^dried specimen). 



HABITAT.— On stones in shallow water in Frederick 

 Museum ^^' ^"^ ^^ presented to the Tasmanian 



PI. I. Figs. 1-4.. 



REMARKS.-This shell is very closely related to A 

 T%rU T^^'^'i ^^^""VJ- ^ ^' S. Aus., 1898, 



Ti.: 1 .i; ; 1^' ^: ""^ ^^'""^ '^ "^^y ^^ ^ g^^^t form. 



The lengtli of their type is only 8 mill., whilst this species 



^UrlTr ^ TiF^^' ^^^? "^^^^-^ ^^^ ^^' therefore, immensely 

 larger. The pustules on the valves are much more 

 numerous, and closely massed together, not separated 



into distinct rows, and are even more elongated: the 

 median valves are also of a different outline, if their figure 



correctly represents it. The girdle in our shell seems 

 wider in proportion, and is very densely covered with a 



"J^"? J" ■ .^^^d.l^like spicules, instead of being ''looselv 



clothed with minute scales." 



A. lachrymosus also resembles A. spectosus, but the 

 tear-drop pustules, and the longitudinal striation of the 

 dorsal areas distinguish it from that species 



