of a few Annelids. 205 



The young of many of our Annelids present a similar con- 

 trast to the adult, the latter passing their existence buried in 

 tubes sunk in the mud or sand, while in their early stages they 

 are free and nomadic, and swarm near the surface of the sea. 

 Who would have thought of looking for young Echinoderms 

 among those erratic beings which perform such a conspicuous 

 part in the phosphorescence of the sea, until the wonderful re- 

 searches of Miiller led the way to a field of investigation which 

 has revealed changes of the most astonishing nature ! The 

 young Crustacea, until quite advanced, find their way to the 

 top of the water, where they swim about in company with em- 

 bryo moUuskSj both very different in appearance and in their 

 habits from the adults. 



From the few complete embryologies we possess of the lower 

 marine animals, it is apparent that there has not been, up to 

 this time, any systematic method of working. Artificial fecun- 

 dation can do much towards adding to our knowledge of the 

 early stages of marine animals; but any one who has lived near 

 the sea-shore and endeavoured to keep alive these tiny creatures, 

 will soon find in this method insurmountable obstacles to pur- 

 suing his investigations beyond very narrow limits. The only 

 way is to go to the fountain-head at once, to make one^s self 

 familiar with the currents at all hours of the tide and under all 

 possible influences of wind, to notice the place where opposite 

 currents meet and throw into long bands the wealth of animal 

 life they have swept along, to become so perfectly familiar with 

 what you may expect to find under certain conditions that no 

 time shall be lost in looking for the most favourable spot, which 

 otherwise you would only stumble upon accidentally. The 

 habitat of the adult animals should be carefully observed, so 

 that, by surface-dredging with the fine gauze hand net in the 

 vicinity of their abodes, and by a close attention to the direction 

 which the currents take from these places, at the time of breed- 

 ing we can often obtain specimens at all ages and of all sizes, 

 till they have ceased to be nomadic or have assumed the habits 

 they retain in their adult condition. 



According to the nature of each locality, spots are easily found 

 where the currents which skirt along the shores are compelled 

 to pass. Projecting points of land are barriers during certain 

 hours of the day, and everything brought floating with the tide 

 along their shores will accumulate, until it forces its way round 

 or over the obstacles. Narrow passages between islets and the 

 shore, through which the tide rushes with great rapidity, will 

 give us a synopsis as it were of all that can be found in the 

 vicinity. When the wind blows constantly from the same di- 

 rection, it will heap up on the lee shore anything floating on the 



