No. 598] SHORTER ARTICLES AND DISCUSSION 



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found to have two living lepad barnacles attached to one of its 

 erectile spines 2 upon the ventral surface two centimeters to the 

 right anteriad of the anus. The Diodon was a small individual, 

 16 cm. long. It was kept under observation in the laboratory for 

 several weeks. 



According to a determination for which I am indebted to Mr. 

 H. G-. Coar, the barnacles belong to the species Conehoderma 

 virgatum (Spengler), although varying "a trifle from Gruvel's 

 type description, but not sufficiently to correspond to Coneho- 

 derma hunteri R. Owen, 1830, which the specimen approached 

 slightly, nor to Leach's (1818) variety chelonophilus of C. vir- 

 gatum." This species has not previously been recorded from the 

 Bermuda area, though it is known over the Atlantic generally 

 and (to judge from statements of fishermen) occurs here upon 

 young turtles. C. virgatum has been found on Mola, ships' bot- 

 toms, and various other objects (Pilsbry, 1907, p. 99), but the 

 present record is somewhat unusual. 



Different semiparasitic lepads have quite various hosts, such 

 as medusa?, antipatharians, the spines of echinoids, molluses, crus- 

 taceans, sharks, teleosts, turtles, the tail feathers of sea birds, 

 whales, and so forth (Pilsbry, 1907; 1910). Those occurring 

 on fishes seem, naturally, to affix themselves to some hard part, 

 for example, the head/ as in the case of Tylosurus (Sumner, 

 Osburn, and Cole, 1913, p. 647). Jordan (1905, p. 341, fig. 226) 

 figures a flying fish with conchodermas attached to a Penella 

 growing on the fish, a condition of double parasitism which has 

 been described for Xiphias. In the present instance, the larger 

 of the two conehoderma individuals (20 mm. long) was found to 

 have its peduncle completely surrounding the spine to which it 

 had become fixed. The second individual was much smaller (4 

 mm. long) and attached to the peduncle of the first. Both speci- 

 mens were so oriented that the opening between the valves was 

 directed toward the head of the fish. The skin of the fish about 

 the base of the spine was inflamed, and the muscles which nor- 

 mally control its elevation for defensive purposes had apparently 

 degenerated. When it was attempted to preserve the Dwdon, 



a The figure of Diodon hystrix, which is used in current lchthyologica 

 handbooks, represents the animal in a semipuffed-up condition and with the 

 frontal spines erected. Alive, the fish has a quite different aspect, all the 

 spines being flattened down to the skin unless the creature is \ 

 turbed. When preserved in formalin it assumes the appearance depicted 

 in the handbooks. 



