46 DE. W. T. CALMAN ON A COLLECTION OF 



they affect Animal Life ' (1881) this Crah is identified with the present species, and a 

 fuller account is given of the " galls " formed by it. These were found on the corals 

 Siderojiora digitata and S. palmata and on species of Seriatopora. He describes the 

 formation of the gall by the growth of two broad flattened branches, and notes that the 

 shape differs according to the species of the coral. " In the Seriatopora both the twigs 

 are leaf-shaped and beset with more or less numerous offshoots terminating in sharp 

 spines. In the more solid Focillopora the twigs also have spines, but they are more 

 massive. Finally, in Sideropjora spines are wholly absent, and the two twigs between 

 which the crab lives are altogether more massive." He describes the gradual closure of 

 the gall by concrescence of the edges, " till at length only two fissures, more or less wide, 

 are left, which plainly show, by their position opposite to each other, that it is through 

 them that the current for respiration passes : one fissure serves for the influx, the other 

 for the exit, of the water ; " and reasons are given for believing that these fissures are kept 

 open owing to the current of water checking the growth of the coral so long as the crab 

 remains alive. 



Semper states that a Hapalocarciniis, " it woiild seem identical in species," occurs at 

 Reunion (p. 281), but I can find no other record of its occurrence there. He also 

 mentions (pp. 217 & 453) certain observations by Graeffe, but no reference is given, 

 and I have failed to trace the source from which he quotes *. 



Bassett-Smith f has described galls formed by a crab on Serlatoporu iinhricata, B.-S., 

 fx'om the Tizard Banlc in the China Sea. The crab is not described, but it probably 

 belonged to the present species. 



Hickson $ has described and figured galls on a Jlillepora containing a crab which he 

 assumes to be Sapalocarclnns. The galls are unlike those described by the authors 

 quoted above, being inflated bulbs with a single, wide, terminal aperture. 



The series of galls examined by me are formed on a sjiecies of Scriatopora §, and the 

 mode of growth agrees well with the descrij)tions of Verrill and Semper. The earliest 

 stage is represented by a specimen (fig. 38) in which the gall is beginning to be formed at the 

 point of bifurcation of a branch. A broad palmate process, slightly concave internally, 



* As certain passages from Samper's work have recently been quoted, without correction, by Hickson, it may not 

 be superfluous to point out that the English edition of this work (I have not been able to consult the German 

 edition) abounds in typographical and other errata. Thus, on p. 216, the date of Stimpson's paper is given as 1837 

 (Stimpson was born in 1S32) instead of between 18.56 and 1859. On p. 217 it is stated that the present species 

 was "discovered in the Pacific Ocean by Dana in the course of his great voyage under tho command of AVilkes."' 

 As a matter of fact, the Bpecimeus were collected (no doubt by Stimpson himself) during the U.S. iS'orth Pacific 

 Surveying Expedition under Capt. .John liodgers. The incidental references to the carrying of the i/ouitr/ in the 

 brood-pouch (p. 217) and to the course of the respiratory current (p. 219) are our only authority for^believing that 

 I/cqialocarcinus differs in these respects from the majority of the lirachyurn. In the explanation of tig. 65 (p. 218) 

 Sideropora hystrix should probably read Seriatopora hystrhr. 



t Ann. Mag. Nat. Hist, ((i) vi. 1890, p. 364. 



X Bull. Liverpool Mus. i. nos. 3 & 4, pp. 81-82, plate. 



§ Prof. F. Jeffrey Bell, who has kindly e.\amined my specimens, informs me that their fragmentary nature 

 renders an exact determination ditKcult, but that they seem to approach most closely to S. clegans, M.-E., though 

 differing from it in certain rliaraeters. 



