784 '^ THETIS " SCIENTIFIC RESULTS. 



Himerometra pcedophora, 1909, H. L. Clark, Mem. Austr. Mus., 

 iv., p. 524, pi. xlvii,, figs. 4-10 (off Manning River, 22 /ms.). 



Differential Character's. — This species is more delicate and 

 slender than P. macronema; the centrodorsal is less thickened 

 and columnar, with the cirrus sockets less regularly arranged; 

 the cirri are shorter and more slender, especially distally, with 

 short proximal segments; the proximal pinnules are more slender 

 and shorter, and all the pinnules have proportionately consider- 

 ably shorter segments. 



Specimens in the Australian Museum Collections. — Port 

 Stephens. — Eighty-four specimens ; a moderate sized specimen 

 has nineteen arms 55 mm. long and the longest cirri 50 mm. long 

 with 94 segments ; the others are of medium size and have 

 between fifteen and twenty arms. 



Nelson's Bay, Port Stephens. — Three medium sized specimens. 



Newcastle, 42-78 fathoms. — One specimen with nineteen arms 

 65 mm. long ; two II Br series are lacking, and one III Br series 

 is developed (externally). 



Newcastle Bight. — Six medium sized specimens. 

 Broken Bay. — One medium sized specimen. 

 Broughton Island. — Two small specimens. 



Off Barranjoey. — One stout medium sized specimen with 

 eighteen arms. 



Off Port Halliday. — One small ten-armed specimen; the arms 

 are 20 mm. long and the cirri about xv., 47-49, 17 mm. long. 

 This specimen is intermediate between the adult form and the 

 ten-armed young called by Dr. H. L. Clark "Himerometra pcedo- 

 phora" ; the smaller cirri are of the undevelo[)ed type character- 

 istic of '^ pcedophoj-a," but the longer have distally taken on the- 

 characters of those of the adult; the cirrus sockets are arranged 

 in two columns in each radial area with a more or less marked 

 midradial space between them as in I'terometra and in many of 

 the Thalassometridse. 



Cape Hawke. — Four medium sized specimens with twelve, 

 fourteen, seventeen and eighteen arms ; the largest has arms 50 

 mm. and cirri 40 ram. long. 



Port Jackson. — Eleven specimens ; one fine large example has 

 nineteen arms 75 mm. long and cirri about 1. 84-90, 60 mm. to 

 65 mm. long ; the centrodorsal is 4 mm. high and 6 mm. broad ; 

 another large specimen has twenty-three arms 70 mm. long and 

 cirri 50 to 55 mm. long ; the smallest specimen has twelve arms 

 30 mm. long. One very curious individual has twenty-three arms 

 about 65 mm. long, all the II Br and three III Br series being 

 developed ; the arms resemble those of ordinary specimens frook 



