37 



The intestinal tube is long, without muscular stomach. The 

 respiratory trees free, but not large ; the ovaries consisting of 

 numerous undivided tubes. 



In answer to a question from Mr. Desor, Mr. Ayres remarked 

 that the Holothuridas present many points of analogy with the 

 other Echinodermata. The suckers, by means of which most of 

 the species move, are of similar organization to those of the 

 Sea Urchins and Star Fishes. Each of these tribes, however, 

 possesses its own peculiar laws in regard to the calcareous 

 deposits, so that from a single sucker it is commonly easy to 

 determine the nature of the specimen. These organs vary in 

 the amount of calcareous matter according to the latitude in 

 which the species live. The plates, also, on many of the Holo- 

 thuridce, closely represent those which form the shell of Echinus, 

 and the allied genera. The oral circle is the analogue, less 

 complicated, of the "Lantern," as it is termed. 



The arrangement of parts in quinary order is found to prevail 

 in this family to a great extent, though there are many excep- 

 tions. The longitudinal muscles are, so far as observed, always 

 five, and the retractor muscles of the same number. The ten- 

 tacula are commonly ten or some other multiple of five. In 

 Synapta^ however, they are in general twelve ; the pieces of the 

 oral circle being always of equal number with the tentacula. 

 Where the oral circle is of a single piece, it presents points 

 anteriorly and posteriorly which are multiples of five. The rows 

 of suckers — where they occur in rows — are generally five, 

 though sometimes two or three of them cannot be traced. 



Mr. Ayres said that he had intended to make these points of 

 analogy the subject of a special communication at some future 

 time. 



Mr. Horatio R. Storer read a description of a new spe- 

 cies of Etheostoma, under the name of Eiheosioma Lins- 

 leyi, as follows : — 



Etheostoma Linsleyi. Color, a uniform dark green, lighter 

 upon sides towards abdomen, serving as the ground for some 

 ten or twelve deep brown, almost black, transverse bands, which 

 are entire at first, but more or less broken towards the tail, and 

 somewhat confluent on dorsum. Head and thorax profusely 

 sprinkled with fuliginous dots. An indistinct dark band de- 



