( 660 ) 



in some regards from one anotlier as well as from tlie .lapaii species. 

 I made the acqnaintance of the latter by studying a few samples 

 which were kindlj' lent me from the Berlin museum by the Director 

 (Prof. K. MoEBius) and by tlie curator of the Crustacea Department 

 (Prof. W. Weltner). 



Apart from Pilsbry '), the Japan species has also been named 

 and described by Fischer ") ; one of the two varieties from the 

 Malay Archipelago has of late again met with the same fate from 

 Annandale '), who ti-ied to introduce it into the literature of the 

 Cirripedia as a new species. 



Yet, though we dispose at present of three names and three 

 fairly extensi\e descriptions for this species, a very curious plieno- 

 menon in the life-history of the reproductive period of this (ScaZ/JcZ/z//» 

 has hitherto escaped the attention of its describers ; for I can hardly 

 believe that they could have discovered this peculiarity and yet 

 not mentioned it in their papers. 



Pilsbry says- of this species (and Fischer in this regard quite agrees 

 with him) that it was found in shallow water in Japan. The speci- 

 mens of the Berlin Museum were from Nagasaki and apparently also 

 from coastal waters. Those of the Siboga Expedition are from four 

 different stations the depths of which range from 204 to 450 m. 

 Annandai.e had a single specimen at his disposal, caught in Bali 

 Straits at a depth of 160 fathoms, about 290 m. 



Scalpellwn Stearnsi belongs to the unisexual species of the genus : 

 the large specimens with fully developed capitulum of a length of 

 about 5 cm. and with (for a species of Scalpellum) \'ery long pedun- 

 cles (of 5 — 9 cm. length) are the females. The males (which should 

 not be called "complemental" males in this case) are looked for in 

 vain at the place they ordinarily occupy, viz., at the inner side of 

 the scutum, near the occludent margin, a little in front of or above 

 the adductor muscle, in a duplicature of the sac or mantle which 

 covers the valves of the capitulum on their inner surface. They are 

 not to be found there — and I think this explains why they escaped the 

 attention of the earlier describers. Darwin discovered that the little 

 males in one of the species (in Sc. rostratuin., Darwin) were attached 

 as three little parasites to the body of the hermaphrodite, close 

 under the labrum, between it and the adductor muscle almost in 

 the median line of the body — but even at that place they are not 



1) Proceed. Acad. Nat. Sci. Philadelphia. 1890. p. 441—443. 



») Bullet. Soc. Zool. d. France. XVI. ^1891. p. 116—118. 



3) Memoirs Asiatic Soc. of Bengal. I. N». 5. 1905. p. 74—77. 



