COMATULJE OF THE MERGUI ARCHIPELAGO. 



3L5 



rior arms in this' in dividual being brought into communication 

 with the peristome. 



It would be interesting to learn to what extent these arms are 

 isolated ; whether, for example, the water-vessel continues on- 

 ward in its normal course, although there is no ambulacrum above 

 it. I think it not improbable that such might be the case, as it 

 certainly is so in the ungrooved and non-tentaculiferous arms of 

 several species. 



The parasitic growths to which I have referred above are of a 

 very singular character. They only present themselves upon this 

 one individual, and occur along some of the brachial ambulacra, 

 blocking them more or less completely. Some of them have been 

 removed and sent to Professor von Graff, who will report upon 

 them separately. 



DESCRIPTION OF THE PLATES. 



Plate XXVI. 

 Figs. 1-5. Antedon Andersoni, sp. n. 



Fig. 1. Dorsal view of the calyx and arm-bases, X 2. 



2. Side view of the second and following brachials, with their pinnules, x 2. 



3. Side view of the lower part of an arm, X 2. 



4. Portion of a brachial ambulacrum, as seen after removal of the pinnules, 



X 4. 



5. The same, with one pinnule in situ, x 4. 



Figs. 6-10. Actinometra notata, sp. n. 



Fig. 6. A disk, with abnormally distributed ambulacra, X 1-fc. 



7. Dorsal aspect of the adjacent portions of two rays in an adult indivi- 



dual, X 2. 



8. Dorsal aspect of the calyx and arm-bases in an immature specimen, 



X 2. 



9. Dorsal view of the middle part of an arm, X 2. 



10. Side view of the second and following brachials, with their pinnules, 



X 2. 



11. A cirrus, X 2. 



12. Another, less mature, X 2. 



Plate XXYII. 

 Figs. 1, 2. Antedon covjungens, Carpenter. 

 Fig. 1. Side view of the second and following brachials in the outer arm of a 

 distichium, with their pinnules, X 3. 

 2. The same part of an inner arm X 3. 



