168 DR. T. DAVIDSON ON EECENT BRACHIOPODA. 



observation, except in Rhynchonella, in whicli there are four, as first pointed out by 



Prof. Huxley two [p. 821] within the ventral, and two within the dorsal valve ; 



both paii's are precisely similar, and are of a yellowish colour .... The central portion 

 of the blood-system in Rhynchonella is arranged much as in the Terchratulldce .... In 

 a. psittacea [p. 829] tlie setae are slender, short, and finely pointed ; they vary in length, 

 as they do indeed in all the species, and occasionally three or four issue out of one 

 follicle .... The great cavity [of the perivisceral chamber], placed close to the hinge of 

 the valves, in which the viscera are lodged, is limited above and below by the dorsal and 

 ventral walls of the body, and in front by the inflections of the inner laminae of the pallial 

 lobes." In conclusion, Mr. Hancock describes at great length the nervous sj^stem, to 

 which we cannot refer. 



Rhynchonella psittacea, var. Woodwardi, A. Adams. (Plate XXIV. figs. 12-13.) 



Rhynchonella Woodivardii, A. Adams, Ann. & Mag. Nat. Hist. 3rd ser. vol. xi. p. 100, 1863. 

 Rhynchonella psittacea, var. Woodwardi, Davidson, Proc. Zool. Soc. 1871, p. 309, pi. xxxi. fig. 12. 



Mr. Adams states in his paper that " this species differs from R. psittacea in being 

 concentrically striolate instead of radiately grooved ; the beak, moreover, is smaller and 

 less curved ; the foramen is more broadly triangular, and the ventral margin rounded and 

 produced in the middle. The young possess the same characters seen in more adult 

 specimens." 



Hah. Gotto, 48 fathoms ; also off Ptifunsiri Islands, four miles from the shore, in 

 35 fathoms, from a bottom of coral, broken shells, and stones. 



I have been able to examine two examples of this shell, given to me by Mr. Adams, 

 and could distinctly perceive faintly radiating striae, similar to those that cover the surface 

 of B,. psittacea. I cannot help thinking, and am confirmed in this opinion by Dr. Gwvn 

 Jeffreys, that thei?. Woodioardi of Adams is no more than a local variety of i?. psittacea. 



The specimens obtained by Mr. Adams are of a less bluish tint than we find usually 

 in the shell last named, but some examples from the Northern European seas have also 

 assumed tliat colour. 



94. Rhynchonella lucida, Gould. (Plate XXIV. figs. 14-15 h.) 



Rhynchonella lucida, Gon]d,'Proc. Boston Soc. Nat. Hist. p. 323, 1800; Otia Concli. p. 120; and 

 Proc. Boston Soc. Nat. Hist. vol. vii. p. 323, 1871 ; E. Suess, Ueberdie Wolmsitze der Brachiopoden, 

 Sitzungsb. k. Akad. Wissensch. Wien, p. 219, 1859 ; A. Adams, Ann. & Mag. Nat. Hist. 3rd ser. 

 vol. xi. p. 100, 1863; Dall, Amer. Journ. of Conch, vol. vi. p. 153, 1870; Davidson, Proc. Zool. Soc. 

 p. 309, pi. xxxi. figs. 13-1 1, 1871. 



Hemithyris lucida, Dall, Proc. Acad. Nat. Sci. Philadelphia, p. 196, 1873. 



Rhynchonella lucida, G. Duuker, Index Moll, maris Japonici, p. 253, 1882. 



Shell small, obtusely subrhomboidal or ovate, rather longer than wide. Dorsal valve 

 convex, almost gibbous ; mesial fold wide, commencing to rise at about half the Icns-th 

 of the valve. Ventral valve rather less convex, or deeper tlian the opposite one, and 

 scooped out near tlie front in the form of a rather deep sinus. Peak acute, sharply 

 incurved ; foramen beneath the angular extremity of the beak, completed by a deltidium. 

 Surface smooth ; shell-structure fibrous. Colour light glassy grey. Length 6 lines, width 

 5 lines, depth 3 lines. 



