PART 5 



A MONOGRAPH OF THE EXISTING CRINOIDS 



159 



TABLE 4. Measurements of some specimens of Antcdon incommoda, respectively three synlypes of 

 A. incommoda austini from northwest Australia, five syntypes and three other specimens of A. in- 

 commoda incommoda from Port Phillip, Victoria, and the types of Compsomctra lacertosa from 

 Port Jackson summarized for comparison 



Description of the types of lacertosa. Centrodorsal discoidal, rather tliin, with 

 a broad flat polar area nearly or quite 2 mm. in diameter; cirrus sockets arranged in 

 two very closely crowded more or less irregular marginal rows. 



Cirri XXXIV-XXXVI, 9-12 (usually 10), 7mm. long; first segment very short, 

 second nearly or quite as long as broad, fourth and fifth the longest, about half again 

 as long as the median diameter; following segments gradually decrease in length, so 

 that the last two are about as long as broad; opposing spine minute, slender, sub- 

 terminal, directed slightly forward; terminal claw long, nearly twice as long as the 

 penultimate segment, evenly tapering and moderately and evenly curved; second 

 and following segments slightly constricted centrally, this character gradually dis- 

 appearing distally as the segments become shorter; longer proximal segments round- 

 ed in cross section and comparatively narrow ha lateral view, the shorter outer seg- 

 ments becoming laterally flattened and therefore appearing broader in lateral view. 



Distal edge of radials even with the border of the centrodorsal. 



IBr! very short, about four tunes as broad as long, slightly trapezoidal. The IBr t 

 (axillaries) are almost triangular, the lateral edges, which are slightly shorter than those 

 of the IBr b making with the sides of that ossicle almost a right angle; in shape they 

 are about as broad as long, with the distal angle considerably produced. 



Arms 10, from 60 to 65 mm. long, rather stout in the basal third but becoming 

 exceedingly slender distally; first brachial short, almost oblong, from two to two and 

 a half times as broad as long in the median line, barely in contact basally interiorly, 

 the diverging interior edges making a very broadly obtuse angle; second brachial 

 much larger, almost triangular, about as broad as the greatest length; first syzygial 

 pair (third and fourth brachials) wedge-shaped, twice as -long ulteriorly as exteriorly, 

 about as broad as the interior length; following three brachials about twice as broad 

 as the median length, slightly wedge-shaped, the brachials then become very obliquely 

 wedge-shaped, almost triangular, about as broad as long, further out on the arm 



