428 PROCEEDINGS OF THE BRITISH ASSOCIATION. 



ago pointed out the development of the Cirrhapods, which are first deposited free, 

 and afterwards become fixed. The letter was from Captain Du Cane, of 

 Southampton, who had been led accidentally to investigate this subject. He 

 had obtained the ova of what he supposed at first to be the Common Prawn, from 

 a ditch to which the sea had access, but on examining the water he found it only 

 slightly brackish, and therefore he inferred it was not the Common Prawn, and 

 proposed to name it the " Ditch Prawn." After keeping these ova for some time 

 they produced a number of minute diaphanous animals, altogether different from 

 the full-grown Prawn. On attentively watching them he found that they assumed 

 different forms as they increased in size. He was, however, unable to trace their 

 changes beyond the third day, as they invariably died at this period. The letter 

 was accompanied by drawings of the various forms the animals had assumed. 

 The President observed that it was generally difficult to keep salt-water 

 animalculae alive, as the water became so soon decomposed. The letter of Capt. 

 Du Cane was valuable, and he hoped that the subject of the development of 

 Crustacea would meet with more attention than it had done at present. He 

 questioned whether many of the received species of Crustacea were any thing 

 more than one animal in its several stages of growth. 



Dr. Richardson inquired if it were not possible for Capt. Du Cane to have 

 mistaken some parasitic animals for the young Prawn ? 



The President replied that he did not think this probable, as the ova were 

 found several times in great abundance, and their development led to the same 

 results. 



The Rev. W. F. Hope suspected the animal whose development had been 

 observed belonged to the Shrimp and not the Prawn family. The Ditch Shrimp — 

 which he suspected this to be — was common on the Norfolk and Suffolk coast. 



Some general remarks then followed by various members on the economy of 

 Crustacea. 



Mr. Halidav exhibited some plates of the Argas and Ixodes, which produced 

 the poisonous bites alluded to yesterday. — The President observed that the term 

 " bite " was improperly applied to the wound produced by these insects. They 

 were the result of the introduction of their long serrated proboscis, and he thought 

 the painful consequences were the result of violently extracting the part from 

 the skin. 



Mr. Babington then read a " Notice, with the Results, of a Botanical Tour 

 in Guernsey and Jersey." He spent two months on the islands, collected about 

 500 species, and obtained a list from Mr. Saunders, nurseryman, of 225 others. 

 Of plants not before recorded he had found the following : — Hypericum lanci- 

 folium, Neottia cestivalis, Sinapis incana, Mercurialis ambigua, Arthrolobium 

 ebracteatum, Atriplex rosea. Of plants common in England he had not seen in 



