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Marvels of the Universe 



BURROWING SEA CUCUMBERS. 



These are two distinct Uinds that agree in their habit of sinking their bodies into the ooze, whilst keeping their mouths 

 above it. Although bearing no resemblance to cucumbers, they may be likened to certain forms of gourd, which are the 

 vegetable cucumber's relatives. 



A MESSMATE OF ANTS 



BY H. ST. J. K. DO\ISTHORPE, F.Z.S., F.E.S. 



Perhaps one of the most interesting beetles which occur in Britain is the subject of this sketch. 

 It is an ants'-nest species, and passes its whole life in the home of its host — the large blood-red 

 Robber Ant, our only slave-making species. The writer was fortunate enough to witness one of 

 its slave raids when at Bewdley Forest, in Worcestershire. Only two other observers, Charles 

 Darwin and Frederick Smith, have seen this before in Britain. The worker ants march in a body 

 from their nest to a colony of a black species of ant. which the}^ have previously located. They 

 attack the latter, kill an\' that offer resistance, and steal the cocoons, which they carry back to their 

 own nest. When the black ants hatch out from these cocoons they act as slaves to their captors. 



To return to our beetle. In 1710 a single specimen was taken by Sir Hans Sloane on Hampstead 

 Heath. A second was found by Dr. Leach, when travelling in the mail coach between Cheltenham 

 and Gloucester, about 1820. Both these specimens are now in the British Museum. It was not 

 found again for many years, and was considered doubtfully indigenous to Britain. On May 25th, 

 1906, the writer discovered it again when investigating a nest of its host, the slave-maker, at 

 Woking, and since then has found it in numbers in the nests of this ant there. On one occasion 

 over sixty individuals were found in a single nest. 



The beetle is a true guest to its host ; that is to say, it is fed by the ants, and supplies them 

 in return with a sweet secretion which exudes from small orifices in the segments of the hind body. 

 It is a reddish-brown creature, with tufts of golden hair, which cover the places from whence the 

 sweet fluid springs. When it wishes to be fed it taps an ant with its feelers, in the same way that 



