34T 



previoiis meeting relative to Amphioxus, read the following 

 extracts from his notes taken while on the United -States 

 Exploring Expedition under Capt. Wilkes : — 



Feh. 3, 1842, Sulu Island in sight (between Mindanao and Borneo). 

 Amphioxus captured ; it was scarcely more than a third of an inch 

 long ; struggled when taken out of the water ; rather stiff like an 

 Ammodytes, and in solidity and motions resembling a fish ; but, when 

 replaced in water and examined with a microscope, the surface of 

 the body, on seeming intercostal spaces, was found occupied by series 

 of vibratile cilice^ continually in motion, and not unlike the so-called 

 " branchiae " of Salpa. 



The animal itself, being transparent, presented interior lines having 

 the semblance of a skeleton. These lines did not appear to be nerves ; 

 for they were devoid of expansions and of gangha. The animal liad 

 no head, eyes, nostrils, mouth, nor brain ; the organ holding the place 

 of a medulla spinalis terminating anteriorly in an obtuse point ; and 

 seemed, besides, devoid of branches. A nervous system, therefore, 

 could not be made out. The absence of a heart was also noted, and 

 of blood-vessels, and all signs of a circulation. 



The so-called " mouth " was much as in Yarrel's figure, and ap- 

 peared to lead into a large cavity occupying the thoraciform portion 

 of the body ; which cavity was continued beyond, and again enlarged 

 into a loose sack, marked with longitudinal Hues or furrows, and, at 

 the extremity, occasionally manifesting a slight retractile movement ; 

 but whether a vent was situated here could not be determined. 

 Above the loose sack was something like an intestine, prolonged into 

 the tail, and containing extraneous substances ; its contractile move- 

 ments seeming too quick for peristaltic. 



Transparency being also incongruous with the class Vertebrata, the 

 conclusion arrived at was, that the Amphioxus is neither a verte- 

 brate animal nor a mollusk. After a brief examination, the specimen 

 was handed to Mr. Dana ; whose figure will probably supply further 

 particulars. 



In consequence of the discovery of an Amphioxus on our own coast, 

 the above observations are offei'ed for comparison, in order that, if 

 possible, the real affinities of the animal may be ascertained. 



Prof. J. Wyman observed that the researches of Quar- 

 trefages and Peters, on the European species of this genus, 

 had proved, beyond question, that this animal is a true 

 vertebrate. 



Mr. Thomas Gaffield made some remarks on tlie action of 

 sunlight on window-glass. 



