MUSEUM OF COMPARATIVE ZOOLOGY. Ill 



The disk in several instances was removed from its connection with 

 the arms, and the tive remaining connected arms lived for three days after 

 the mutilation. 



I had some difficulty in identifying the adult Amphiura, from the fact 

 that in some of the best descriptions of A. sqaamata the color of the live 

 animal is not given, while in others it is recorded as white.* None of the 

 adults of A. squamata studied were white, but all were brown or choco- 

 late colored when alive. Variation of color is great among specimens of 

 the same genus, and in some localities this species may be while; bu!^ 

 the specimens which were studied were not. white. 



II. THE BILATERALLY SYMMETRICAL LARVA. 



August Krohn t and Max Schultze J first found out tliat Amphiura 

 (Ophtolepis) squamata, Sars, is viviparous ; and that discovery has been 

 established without possibility of doubt by Sars,§ Lyman, || Metschni- 

 koff,ir Apostolides,** Ludwig,tt and others. Its viviparous life falls into 

 the following divisions: (1) The development of the bilateral larva; 



* Packard states (Zoology, p. Ill) : "A. squamata, Sars, has long slender arms 

 and is white." In Agassiz's "Sea-Side Studies," p. 115, A, squamata is spoken of 

 as the "white Amphiura." 



The adults were identified by comparison with specimens in the Museum of Comp. 

 Zoology identified by Mr. Lyman, and by reference to published descriptions. Prof. 

 Verrill has also examined my specimens of the adults, and verifies my identification. 



+ Ueber die Entwickelung einer lebendig gebarenden Ophiure, Arch. f. Anat. 

 Physiol, u. Wiss. Med., 1851. Krohn first showed that Amphiura (Ophiolepis) 

 squamata is viviparous. 



The first naturalist to describe the young oi Amphiura {Ophiolepis) squamata was 

 Joh. MiiUer {Arch. f. Anat. Physiol, u. Wiss. Med., 1851, p. 1 et scq.). He errone- 

 ously ascribed to Ophiolepis in this place a pluteus form. Following Krohn's paper 

 (op. cit., p. 353), where Ophiolepis (Amphiura) squamata is shown to be viviparous, 

 it is acknowledged that the young described by Miiller is of some other Ophiuran, 

 and not Ophiolepis squamata. 



t Ueber die Entwickelung von Ophiolepis squamata, einer lebendig gebarenden 

 Ophiure, Arch. f. Anat. Physiol, u. JFiss. Med., 1852. 



§ Jahresbericht of Leuckart, 1865, p. 86. 



II OphiuridEe and Astrophytidse, III. Cat. Mas. Comp. Zool., No. 1. 



H Oj}. cit., p. 13. 



** Op. cit. 



tt Zur Entwickelungsgeschichte des Ophiurenskelettes, Zeit. f. Wiss. Zool., 

 XXXVI. 



