134 Transactions of the Society. 



a very tenacious but very costly cement in holding the stones 

 together. If he accomplished this well, he would receive credit 

 for great intelligence and skill. Yet this is exactly what these 

 little ' jelly-specks ' do on a most minute scale, the tests they 

 construct, when highly magnified, bearing compai'ison with the 

 most skilful masonry of man. From tlie same sandy bottom one 

 species picks up the coarser quartz grains, cements them together 

 \\ii\i phosphate of iron secreted from its own substance, and thus 

 constructs a flask-shaped ' test ' having a short neck and a single 

 large orifice. Another picks up the finest grains and puts them 

 together with the same cement into perfectly spherical ' tests ' of 

 the most extraordinary finish, perforated with numerous small 

 pores, disposed at perfectly regular intervals. Another selects the 

 mimitest sand-grains and the terminal portions of sponge-spicules, 

 and works these up together — apparently with no cement at all, 

 by the mere ' laying ' of the spicules — into perfect white spheres, 

 like homceopathic granules, each having a single fissured orifice. 

 And another, which makes a straight, many-chambered ' test,' tliat 

 resembles in form the chambered shell of an orthoceratite — the 

 conical mouth of each chamber projecting into the cavity of the 

 next — while forming the walls of its chambers of ordinary sand- 

 grains rather loosely held together, shapes the conical mouths of 

 the successive chambers bv firmlv cementing together grains 

 of ferruginous quartz, which it must have picked out from the 

 general mass. 



" To give these actions the vague designation 'instinctive' does 

 not in the least help us to account for them, since what we want 

 is to discover the mechanism by which they are worked out ; and 

 it is most difficult to conceive how so artificial a selection can be 

 made by a creature so simple." (Here follows a description of the 

 tube-building of the marine worm Terehella, a far more highly 

 differentiated organism, which again suggests comparison with the 

 wonderful skill of the caddis-worms in the selection and mechanical 

 adaptation of the fragments of plant-stalks, shells, and chopped 

 weed used by various species in the construction of their tubes or 

 cases.) "We can only surmise," Dr. Carpenter continues, "that 

 in the humble Rhizopods, as the whole of each 'jelly-speck' 

 possesses the attribute of contractility elsewhere limited to muscles, 

 so may the attributes which are restricted in the higher types of 

 animal life to the nervous apparatus be there diffused through 

 every particle — the whole protoplasmic substance being endowed 

 in a low degree with that power of receiving, conducting and 

 acting upon external impressions which is raised to a nmch more 

 exalted degree when limited or specialized in the nervous 

 system." 



Every word of Dr. Carpenter's reflections (of forty years ago) 

 on the architectural and selective skill of the Foraminifera appears 



