488 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



the distal cirrus segments and the absence of lateral contact between the IBr t , al- 

 though the postradial series are only slightly separated. 



In 1891 Hartlaub placed Antedon lepida under the synonymy of Antedon palmata 

 ( Lamprometra klunzingeri). He said that the differences between lepida and 

 palmata are not significant, and the two specimens described as lepida are apparently 

 young individuals of palmata. They are not sexually mature. Apart from their small 

 size they are characterized by having the IBr, entirely free laterally, a feature that 

 he had not seen in any specimen of palmata. In addition, P 3 is almost as long as P 2 , 

 and finally, in one of the specimens at least, the spines on the distal cirrus segments are 

 more sharply differentiated than in any specimen from the Red Sea that he had seen. 

 In 1910 I examined the two cotypes of Antedon lepida at the Hamburg Museum and 

 found them to represent the present species. 



In the Challenger report Carpenter mentioned Antedon protecta from Tonga and 

 Fiji in various places, regarding it as a valid species. He said that he had a specimen 

 that he owed to the kindness of Prof. Sven Lov6n. In this the first two pinnules on 

 the outer side of the outermost arms arising from every IIBr series are greatly larger 

 than the corresponding pinnules on the inner arms. P 2 has 25 segments and reaches 

 12 mm. in length, nearly three tunes the length of its fellow on the inner arms. 



In the key to the species of the Palmata group Carpenter placed protecta with 

 conjungens, aequipinna, laevicirra, and imparipinna, these species being distinguished 

 by having two or more axillaries beyond the IBr axillary, P 2 larger than P 3 , the post- 

 radial series free laterally, and P 2 with 25 or more segments, which are not specially 

 elongated. These five species he arranged in two groups, one, in which the lower 

 pinnules are larger on the outer arms arising from each IIBr axillary than on the 

 inner, including protecta and conjungens, and the other, in which the lower pinnules 

 are fairly uniform in size on all the arms, including aequipinna, laevicirra, and im- 

 paripinna. In protecta P 3 was said to be quite short, while in eonjungens P 3 is not 

 especially short, being nearly as long as P 2 on the inner arms. He mentioned the 

 characters of protecta in his discussion of Antedon conjungens, and later said that 

 Antedon similis resembles protecta rather than conjungens. 



The specimen from Tonga in the British Museum is typical. 



Hartlaub in 1890 described Antedon protecta (Liitken, MS.) as a new species, 

 possibly synonymous with Antedon imparipinna Carpenter, from the Indian Archi- 

 pelago and Polynesia, in the following terms: The centrodorsal is from moderately 

 large to large. The cirri are XXV-XLVI, 22-25, and are arranged in two, or in two 

 and a partial third, rows on the centrodorsal. The cirrus segments are of fairly 

 equal size. The opposing spine is feeble. The radials are partially or entirely 

 concealed. The IBri are short and are partially united laterally. The IBr 2 (axil- 

 laries) are pentagonal. The postradial series are mostly in fairly close lateral contact. 

 The outer edge of the postradial series is occasionally crenate. The postradial series 

 divide three times. There are usually nearly 40 arms 70 mm. long. Most of the 

 brachials are triangular and bluntly wedge-shaped. The second syzygy is from 

 between brachials 13 + 14 to between brachials 17+18, and the distal intersyzygial 

 interval is from 8 to 11 muscular articulations. The outermost arms arising from each 

 IIBr axillary bear larger lower pinnules than the inner arms. P, is slender, with 

 12-35 segments, and is about as long as P 2 . P 2 is much thicker, moderately stiff, and 



