72 



COLLINGE : ON THE ANATOMY OF APERA BURNUPI. 



to regard the Testacellid resemblances of Aiopos as independently 

 acquired, in fact I think when we know more of their minute structure, 

 it will probably form a very interesting example of parallelism in 

 evolution. 



In the three specimens of Apera which I have examined, I have 

 seen nothing which might be compared with the spider-glands of 

 Simroth, which have been described as common to Atopos, while the 

 pallial complex, pedal gland, and generative organs are totally different. 



Further, the above authors are, in my opinion, incorrect in stating 

 that Heynemann was wrong in supposing that the orifice near the 

 right upper tentacle was common to the male and female organs. 



I venture to appeal to malacologists and others in South Africa, 

 for more examples of AiJera, in order that anatomical investigations 

 at present in hand may be carried out. 



Figure of the Generative Organs oi Aj^rra hurmtpi, E. A. Smith. 



