1889-90.] On tJie Echinoidea or Sea-UrcJiins. 341 



dropped to the ground. Keen must have been the disap- 

 pointment of the spider in the morning to find that his in- 

 genuity and labour had come to nought. On realising the 

 situation he appears to have finally given up all idea of using 

 stones in the construction of his web. He, however, of new 

 put his house in order, by making his web considerably 

 smaller, and so perhaps in this way remedied the defect in 

 its structure which the presence of the stone was intended 

 to counteract. The spider continued to occupy the same 

 premises till about the middle of October, when it disap- 

 peared from view ; but a small coating of tough webbing, 

 about the size of a shilling, in a corner of the box, marks the 

 spot where the spider has retired for the winter, to issue 

 forth when the warm weather brings about the reappearance 

 of the insects on which he feeds. It will be interesting to 

 note how he constructs this season's web, and we may obtain 

 from an observation of his movements some additional light 

 on the vexed question as to whether the ingenuity displayed 

 by so many of the inferior creatures is on their part instinct 

 or reason. 



^\.—0N THE EGRINOIBEA OB SEA-URCEINS. 



(With Special Eefeeence to those of the Firth of Foeth.) 



By Mr JOHN LINDSAY. 



{Read Feb. 3G, 1890.) 



Summer visitors to our coast -towns sometimes observe, in 

 the " cottage by the sea " which forms their temporary quar- 

 ters, a quaint chimney-piece ornament, in shape somewhat 

 like a melon, divided into vertical zones, and marked all over 

 with numerous lines and dots. This ornament is generally 

 regarded with a certain degree of wonder by the city-dweller, 

 when seen for the first time ; and on inquiry at its possessor, 

 the information may be hazarded that it " once lived in the 

 sea," but beyond that elementary fact, little or nothing to 



