ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 
207 
Echinoids and Asteroids and that in Crinoids aro incorrect. This is 
revolutionary indeed, in face of the speculations and generalizations of 
the last twenty years. 
Bipinnariae from the English Channel.* —Mr. W. Garstang records 
the discovery near Plymouth of JBipinnaria-larvfe of the type described 
by Sars in 1846, and, since then, not known to have been found. Those 
which form the basis of the present paper agree with Sars’ B. asterigera 
in the great development of the pre-oral lobe, but they resemble the 
commoner type and differ from Sars’ larva in the less concentrated 
arrangement of the paired ciliated arms. So far as th& author’s experi- 
ence goes, the mode of swimming is quite unique. During locomotion, 
which is usually in an upward direction, the pre-oral lobe is anterior, 
and the body itself is held quite rigid. Movement is effected by seem- 
ingly indolent, but regularly repeated strokes of the dorsal arm of tho 
pre-oral lobe in an antero-posterior direction over the back of the larva. 
The number of strokes during three consecutive minutes were 80, 81, 
81. The ventral arm and all the paired processes of the body were 
entirely inert, but the arm may play the part of an anterior rudder. 
Mr. Garstang points out that a great development and specialization 
of the pre-oral lobe for locomotive purposes is found in Balanoglossus , 
though all traces of ciliated bands are lost in the course of its develop- 
ment from Tornaria. The existence of Asteroid larvae in which the 
pre-oral lobe is specially developed for the purpose of swimming in the 
open sea seems to the author to point to the idea that the pelagic 
ancestor of Balanoglossus was also provided with a muscular, pre-oral, 
flexible lobe, bounded by the two ciliated bands, and used for swimming. 
In Balanoglossus , after the adoption of life on the sea-bottom, the pre- 
oral lobe, developed under pelagic influences, was used for moving about 
in the mud, where it rapidly lost its primitive ciliated bands. 
Holothurians of North Atlantic.! — Dr. E. von Marenzeller has 
published a detailed account of the Holothurians collected by the Prince 
of Monaco in the Bay of Biscay and off the Azores ; to the preliminary 
notice of this paper we have already called attention. Fourteen species 
in all were collected. The new species Rolothuria lentiginosa was 
represented by a single example, which was 160 mm. long; it is allied 
to H. signata , R. Polii , &c. The examples of H. verrilli show how much 
the cabinet naturalist is dependent on the collector ; specimens simply 
put into alcohol measured 110 mm. long, and had the skin deeply 
creased ; while others, which had been injected with alcohol after ligature 
of the vent, were 200 mm. long and had the skin smooth. This species 
appears to be closely allied to H. intestinalis. 
Benthodytes janthina , though presenting signs of close affinity to 
B. abyssicola, is certainly distinct from it ; the single specimen found 
was a female. A study of Peniagone azorica serves to show that the 
genera Bljpidia and Peniagone should be united. There are some inter- 
esting notes on the much misunderstood species Cucumaria Montagui. 
The discovery of Chiridota abyssicola at a depth of 2870 metres is the 
* Quart. Journ. Micr. Sci., xxxv. (1894) pp. 451-60 (1 pi.). 
f ‘Resultats des Campagnes Scientifiques, &c.,’ vi. Monaco, 4to, 1893, 24 pp., 
2 pis. 
