482 Mr. Edward Heron-Allen [May 21, 



assumed by (81. H4:) Hyper am mina ramof^a, a species which ramifies in 

 a most remarkable manner, so much so that Mr. Earland once con- 

 structed for me a Christmas greeting slide (SL 85) out of its many 

 vagariant forms. (The " selection " in this case is rather that of 

 Mr. Earland than of the Rhizopod.) 



The genus Marsipella, of which the most familiar form is J/. c?/li/i- 

 drica (SL 8G), is built up of sponge spicules set parallel to its axis, 

 and is excessively friable, perfect specimens being very seldom 

 found. It consists of a simple tube affording an easy prey to 

 parasitic worms. It has consequently learnt to protect itself with a 

 crown of spines (SL 87), which keep out these intruders. But some 

 individuals, to which we have given the specific name 31. spiralis 

 (SL 88), have made the same discovery as did the prehistoric genius 

 who invented string (SL 89). Tbey increase their power of resist- 

 ance to shock by twisting their spicules into a left-handed spiral 

 (SL 90), by which means their power of resistance is enormously 

 increased.^ 



But probably the zenith of purpose and intelligence is reached 

 by the genus Technitella, a genus named by Canon Norman— the 

 Little Workman — with good cause. The most familiar species, 

 T. legumen (SL 91), builds its shell apparently of sponge spicules set 

 parallel to its axis. The accidental smashing of a specimen, however, 

 revealed to us the fact that only the outer layer of spicules is thus 

 disposed (SL 92). The inner layer is set at right angles to the outer, 

 thus producing the nearest approach to the woof and warp of a 

 textile fabric possible in so rigid a material as sponge-spicules. This 

 is clearly seen (SL 93j in a highly magnified fragment of a broken 

 shell. The genus reaches its highest development of purposive 

 selection, however, in our species T. thompsoni (SL 94), which, out of 

 the vast and heterogeneous mass of material at its disposition, selects 

 only the anchor-plates of a particular kind of Echinoderm, which it 

 cements together at their edges with an invisible cement, and thus 

 constructs what is certainly one of the most decorative, and certainly 

 the most highly perforated shell in existence.- 



In the presence of the phenomena which I have exhibited before 

 you this evening there are zoologists who aver that there is no such 

 thing as purpose or intelligence to be postulated as a motive for the 

 behaviour, not only of the Protozoa, but even of much higher orders 

 of animal life. Jules Fabre, who has by consent assumed the purple 

 among the historiographers of the Insect World, denies intelligence 

 even to the Digger Wasps, and to the Termites of Ceylon — at the 



^ E. Heron- Allen and A. Earland, On some New Astrorhizidae and their 

 Shell Structure, Journ. R. Micr. Soc., p. 382. 1912. 



2 E. Heron-Allen and A. Earland, On a new species of Technitella from 

 the North Sea, Journ. Quekett Micr. Club, ser. 2, vol. x. p. 403. 1909. 



