Echinocheres globosus, n. gen., n. sp., 
a Copepod parasitic in spines of an Echinothurid. 
By 
H. J. Hansen. 
With Plate XV. 
Åbvout one year ago Dr.,Th. Mortensen showed me a misshapen 
secondary spine of Calveria gracilis (Ag.); the specimen had been 
secured near the Philippine Islands by the ,,Challenger". The distal 
portion of the spine was somewhat thickened, and Dr. Mortensen 
had discovered that a small Crustacean inhabited a cavity in the 
swelling. He asked me to work it out, which I promised, but 
wished for more material. Dr. M. wrote to Prof. F. Jeffrey Bell 
at the British Museum, asking him to send some additional spines 
with the end thickened; these spines have been given him very 
obligingly, but only one of them contained the Crustacean. 
I. The Habitation of the Parasite. 
Of the two spines one was treated with very diluted muriatic 
acid in order to dissolve the chalk; the swelling of the other spine 
has been cut longitudinally with a knife, and this section, with the 
animal in its natural position, is shown in fig. 2. The first-named 
spine (fig. 1) measured 9.2 mm. in length; scarcely its distal fourth 
was thickened, with the diameter nearly twice as long as that at the 
middle of the spine. In both spines the end was truncate, and the 
