52 Animal Ltfe by the Sea-shore. 



of our readers may be surprised to hear, several essentially 

 marine representatives occur on our coasts, forming rare excep- 

 tions in this by far the most numerous of all groups of animals. 

 The five principal will be mentioned liere. Three belong to the 

 order Coleoptera, or Beetles, in which (normally) a pair of 

 membranous wings folds wlien at rest under a pair of hard 

 sheaths known as elytra. One of these is called At'pus marimis 

 or fulvescens (Fig. 63) ; yellowish-brown in colour, one and a-half 

 to two lines in length, with the eh'tra nearly entireh' covering the 

 abdomen as in the Ground-beetles (Carabidce), to which it is 

 related ; the e3'es are minute, partly covered by a shield ; wings 

 are absent. The second, Aepus robtni or hrachelytra, is 

 distinguished \>y shorter elytra. The third, Micralymma 

 hrevipenne, is sligfitly larger and has the eh'tra still more recluced, 

 the abdomen being nearly entirely exposed aboA'e and covered 

 with hard transverse lamellfe ; its nearest ally is the common 

 black Cock-tail (Rove-beetles, Siaphylinidce). These tinv beetles 

 hide under stones that are covered by the sea for several hours 

 every day, or even, at neap-tides, for several days in succession. 

 As their respiratory organs do not differ from those of other 

 insects, thej? probabty ha^'e to suspend respiration, unless 

 enougli air remains in form of bubbles attached to the hairs 

 of the body ; but Acpiis is jn'ovided with a pair of air-sacs in 

 the abdomen, affording, no d(jubt, a reserve ol air for prolonged 

 submersion. The fourth marine insect to be mentioned is 

 Anurida ■maritima (Fig. 64), of the group Colleinbola (f^rder 

 Apiera), small wingless creatures undergoing no metamorph<«es 

 (contrary to the general rule in insects), the more tA-pical forms 

 being called " Spiny-tails," from their habit of leaping b}' means 

 of a forked appendage to the abdomen, appearing as a pair of 

 bristles. This appendage is, however, absent in Anurida 

 (a name meaning " tailless "), a minute black insect only one line 

 in length, found creeping about rocks and under stones, or 

 floating on the surface of small rock-pools, and retreatijig into 

 narrow fissures or emptv barnacle-shells when the tide rises ; 

 in such a shelter, whence it cannot be dislodged b\' the waves, 

 it ma}' remain hours under \vatcr. The fifth exam]ile, Mnchilis 

 marUima, belongs to another group of Aptera, the Thysannra 

 or Bristle-tails, and measures a quarter of an incli in length : 

 it is distinguished from Anurida by the three long bristles in 

 which its abdomen terminates, the median being nearly? as long 

 as the body ; the antennse are also very l<:>ng. This insect is 

 found abmit r<icks, sometimes under stones, sometimes on the 

 sides (if a r<.ick-piH(l, running along swiftly or leaping when 



