Zoologi/.} NATURAL HISTORY OF VICTORIA. [Echinodermata. 



Plate 100. 



GONIOCIDARIS TUBARIA (Lam. sp.). 



[Genus GONIOCIDARIS (Desors.). (Sub-kingdom Radiata. Class Echinodermata. 

 Order Ecbinoidea. Sub-order Desmosticha. Family Cidaridae. Sub-family Goniocidarinte.) 



Gen. Char.— Test high, often higber tban broad ; coronal plates numerous ; primary 

 tubercles perforated, with smooth base. Ambulacra narrower than in other genera of the 

 family ; two porous bands nearly as broad as the intervening median ambulacral space ; middle 

 of the ambulacral and inter-ambulacral spaces bare, sutural edges of the ambulacral and inter- 

 ambulacral plates sunk, forming zigzag depressed lines and pits at the angles of the plates, in 

 which large spherical-headed pedicellariae are lodged, one often to each pit. Spines cylindrical, 

 often cupped at the tip, the sides tubercular or spinose, the thorny spinules often enlarged in 

 whorls near tip of primary spines.] 



Description. — Test moderately depressed. Primary tubercles eleven * in each 

 vertical row; serobicular space transversely oval; mammary boss small, not promi- 

 nent; a row (or, in some parts, two rows) of secondary tubercles round the 

 serobicular area, l to 6 rows of small miliary tubercles concentric with the row of 

 secondary serobicular tubercles on inner end of each inter-ambulacral plate, but a 

 wide smooth margin to each plate forms smooth sunk zigzag- line down middle of inter- 

 ambulacrum ; a narrow band of 3 or 4 rows of miliaries, between primary tubercle and 

 band of ambulacral pores. Primary spines thick with blunt swollen tips, more or less 

 flattened, those of vertex funnel-shaped at tip ; the tip often with a radiating row 

 of thorny spines ; others cylindrical or flattened, and variously terminated by a 

 fringe of longitudinal lamilloe; the underside generally smoother and flatter than 

 the upper; all with conical, thorny spines on upper side, while their lower side has 

 irregular, longitudinal rows of blunt tubercles, or is quite smooth towards the mouth; 

 small primary spines nearest the mouth flat and smooth above and below, both sides 

 serrated with a row of spines, tip bluntly truncated ; secondary spines and papillse 

 flat, smooth, with wide, flat truncated tip; all the spines show irregular, longi- 

 tudinal, obtusely granular lines under the lens. Plates of vertex, or abactinal 

 system, with broad, smooth, sutural margins, but covered with miliary granules in 

 centre; genital plates with very small ovarian opening near middle of central patch 

 of miliary granules; ocular pores very small, double; ambulacra with broad bands 

 of pores and a sunken, middle portion bare along centre, with two or three irregular 

 rows of miliary granules at sides," within the two rows of secondary tubercles which 

 border the two bands of pores. Colour : Plates brownish ; primary spines yellowish 

 or white-pinkish cream colour, with the tubei'cles and thorny spines red, chiefly on 

 underside towards tips ; secondary spines and papillae rich cinabar red, yellowish at 

 tip ; pedicillaria pale dull red. Measurements : Diameter of test of an average 

 specimen, 2 inches 6 lines ; in proportion to diameter, taken as 100, depth of test 

 ^Q^^, diameter of oral aperture, or actinostom ^%^,j, diameter of abactinal system or 

 group of plates on vertex ^^j, length of cupuliform spines round vertex j^^^, width 

 of ditto at tip ^%, length of longest spines at middle jVo ^^ to^o> width of ditto 

 ^^, width of ambulacra at middle ^5_5__^ middle portion of ditto between the bands 

 of pores Ywo) width of inter-ambulacra at middle -j%^, width of serobicular area at 

 middle -^q, diameter of perforated primary tubercle at middle jfo^. 



Reference. — Cidarites tubaria (Lamk.) Anim. sans Vert. 



* Ales. Agassiz states the number to be elgbt (Rev. Ecli. p. 39T). 

 Vec.TL. [ 33 ] E 



