44 



Character of Aleock's Species. Characters of Caligorgia vertir.illata, Pallas. 



c. Ou a centimetre of the twigs there c. On a centimetre there are only 5 or G 



are 8 to 9 whorls of polyps. whorls. 



d. The length of the contracted polyps d. The length of the contracted polyps 



is 075 mm. or less. is 1 to 1"25 mm. 



e. The distance between the successive c. This distance is 1 to 1 '5 mm. 



whorls of polyps generally varies 

 from 0"4 to 0'9 mm. 



Aleock's species is more delicate, with much smaller polyps ; the whorls are 

 more numerous. In the details of the polyps there are also some differences. In 

 C. verticillata the exposed surface of the polyps is covered by four well-developed 

 longitudinal rows of scales, a pair of abaxial and a pair of lateral rows. These last 

 rows are somewhat reduced in Aleock's species, where they are each represented 

 Ijy only three scales, two distal and one basal scale. The inner lateral rows are 

 nuicli reduced in both species. 



The new species may also be easily distinguished from all the dichotomously 

 branched species of Caligorgia hitherto described, viz. C. ventilahrmn, C. mvdesta, 

 and C. compressa ; it is more delicate, with smaller polyps, and none of these three 

 species has so few polyps in each whorl, even on the thinnest twigs. 



There are, however, two new species in the collection made by the Siboga 

 Expedition under the direction of Professor Max Weber in the Malay Archipelago, 

 which in their habit, the dimensions of the polyps, and the small numl^er of polyps 

 in each whorl, much resemble Aleock's species. Tliese are described in my mono- 

 graph on the " Primnoidae of the Sil)oga Expedition " ; in the present note I can only 

 point out the more important differences between these species and this new species. 



One of them, Caligorgia minuta, is distinguished by the much larger and less 

 numerous scales in the polyps ; the abaxial rows consist of only 5 scales each, against 

 7 in Aleock's species ; and of the outer-lateral rows only one distal scale is left, 

 against 3 scales in Aleock's specimen. The operculum in C. minuta is a much 

 lower cone. 



The other new species, C. similis, very much resembles Aleock's species ; but 

 still it seems to me, so far as I can judge from the small material at my disposal of 

 both species, that they are different. The differences are stated in the following 

 taljle : 



Characters of Aleock's Hpccies. Characters of C. similis. 



a. The polyps are arranged in whorls of a. The polyps are arranged in whorls of 3, 

 2, less often of 3.^ very rarely 2, ou the thinner twigs ; 



on the thicker branches the whorls 

 number 4, perhaps also 5 jjolyps. 

 ^ On tlie larger branches tJu'ee was the usual number. — J. A. T. 



