406 Scientific Proceedings, Royal Dublin Society. 



EXPLANATION OF PLATES XVI., XYII., and XVIII. 



Peachia taastata (Grosse). 



PLATE XVI. 



Fig. 5.— Upper view of concliula with six simple lobes ; same specimen 

 as PI. XVIL, fig. 2. 

 ,, G and 7. — Upper views of more complex conchulae. 

 ^^ 8. — Side view of a complex concliula. 



[All the above are greatly enlarged and not drawn to scale.] 



PLATE XVIL 



Fig. 1. — Side view of animal in an ordinary position ; natural size. 

 ,, 2. — Diagrammatic view of tentacles and conchula. — G. Y. D. 

 ,, 3. — Appearance of Peachia hastata in its burrow, looking down 



vertically upon it ; magnified. 

 ,, 4. — Three tentacles illustrating the different appearances due to 



extension, illumination, &c. ; enlarged. 

 ,, 5. — Details of markings on a single tentacle and radius; enlarged. 



PLATE XVIII. 



Fig. 1. — Animal projecting from the sand, tentacles retracted, promi- 

 nent conchula, showing markings on capitulum ; enlarged. 



,, 2. — Capitular markings of another specimen ; enlarged. 



,, 3. — Inflated physa, with slit-like spots ; greatly magnified. 



,, 4. — A still greater state of distension, with circular spots ; greatly 

 magnified. 



, , 5 and 6. — Showmg variations in form ; two specimens ; natural size. 



,, 7. — Illustrating the way in which the animal burrows into the sand. 



