574 Verrill, Notes on Radiata. 



Pectinura maCUlata Vemll, Amer. Jour. Sci., xlviii, p. 431. 



Ophiaraclina maculata Verrill, Proc. Boston Soc. Nat. Hist., xii, p. 388, 1869. 



Dr. Ltitken has adopted the name, Pectinura Forbes {non Heller) 

 for the genus to which this large species from New Zealand belongs. 



ASTERIOIDEA. 



Oreaster occidentalis VemU, (pp. 278, 374). 



Pentaceros occidentalis Verrill (by err. .r), Am. Jour. Science, xlix, p. 99, 1870. (Cor- 

 rected to Oreaster occidentalis, p. 227).* 



Of this hitherto rare species 21 specimens of various sizes have 

 been received from La Paz, They show but little variation except 

 that due to age or state of preservation. Some specimens are so 

 dried as to leave the disk and rays plump and rounded above, while 

 in others the interradial spaces are so shrunken as to make both the 

 rays and disk angular. In some most of the upper and part of the 

 lower marginal plates bear small obtuse spines or tubercles ; in others 

 there are few or none of these ; the two smallest specimens have none, 

 though others, scarcely larger, have quite a number. The smallest 

 specimen has the longer radius 1 inch ; the shorter '50. This, how- 

 ever, has nearly the form and all the essential characters of the adult, 

 though the spines and tubercles are less numerous. 



Nidorellia armata Gray, (pp. 2 so, 372). 



Numerous specimens of this species were received from La Paz, 

 where it is common at the depth of a few fathoms. 



The La Paz specimens present all the variations desci'ibed in those 

 from Panama. Some of the larger ones are unusually spinose, hav- 

 ing large triangular groups of spines on the interradial regions of the 

 upper side, and in some cases three rows of large spines on the rays. 



Gymnasteria spinosa Gray. 



Annals and Mag. Nat. Hist., 1840, p. 278; Synopsis of Species of Starfishes in Brit- 

 ish Museum, p. 8. 1866; Verrill, Proc. Bosbm Soc. Nat. Hist., xii, p. 384, 1869. 



A starfish collected at La Paz by Capt. Pedersen, seems to be iden- 

 tical with this species, originally obtained at Panama by Mr. H. Cum- 

 ing. There are three specimens in the collection. 



Form pentagonal, with rather broad, tapering, somewhat depressed, 

 triangular rays. Radii as 1:22. The skeleton consists of moderately 



* The name, Pentaceros, was used for a genus of fishes by Cuvier and Val. (vol. iii, p. 

 30, 1828 ; ^ee also Giinther. Catal. Pishes of British Museum, i, p. 212) long before it 

 was employed by Gray for this genus. For this reason Oreaster was substituted by 

 Miiller and Troschel. 



