160 THE PROCEEDINGS OF THE LINNEAN SOCIETY 



in double irregular vertical rows. Pores at the sutures in- 

 distinct in the median A. and I, spaces, but well-defined at the 

 junction of the porif. zone and I. plates. Spines thin, slender, 

 short. 



MlCROCYPHUS MACULATUS. AgaSS. 



In the I. space the central part of the coronal plates have a 

 bare lozenge-shaped area parallel with the horizontal sutures of 

 the plates. These spaces rapidly decrease towards the ambitus, 

 and disappear on the actinal surface where the tubercles are 

 larger, occupying the whole surface of the plates. The general 

 color of the test is greenish yellow, with bright violet bare sutural 

 spaces. Diam., 11 to 37 mil. This species is tropical, but I have 

 seen one specimen only which was said to come from the coast of 

 N. S. Wales. 



MlCROCYPHUS zigzag. Agass. 



Much smaller and more globular than the preceding. In the 

 I. space the tubercles cover, as a triangular shield, the greater 

 part of each plate, leaving the median space, and a short length 

 of the horizontal sutures bare from the anal system almost to 

 the actinosome. Sutural pores small, often wanting. Porif. zone 

 and tuberculiferous parts greenish yellow ; bare spaces, dark 

 chocolate color. Diam., 12 to 25 mil. I have seen specimens of 

 this species in Tasmania, where it was thrown up on the sand ; 

 and I have found it myself at Port Denison, N. Queensland. 

 There are specimens from West Australia and Tasmania in the 

 British Museum.* 



Genus 3. — Salmacis. Agass, 1841. 



Test somewhat conical and thick ; pores trigeminate, tubercles 

 crenulate, not perforate, in several vertical rows and 'primary 

 regular horizontal rows as well. A. system broad ; median I. 

 spaces frequently bare, angular pores at junction of plates; abactinal 

 system prominent ; actinosome small, with slight indentations ; 

 spines short, slender, finely striated. Auricles high, thin, with 

 high connecting ridges and small foramen. 



* Agassiz Revision of the Echini, page 146. 



