G30 THE TIMBER-BORING SHRIMP, OR GRIBBLE. 



Several of these species take possession of corallines, each selecting a particular 

 branch, and not permitting any other to intrude upon its premises, fighting with great 

 valour against any assailant. 



They resemble the fly-catchers in some of their habits, sitting patiently on their 

 branch until they see some little creature passing within reach. They then dart at their 

 prey, seize it, return with it to their resting-place and there eat it leisurely. They sit in 

 a curious erect attitude, swaying the body about and occasionally cleaning the antennas 

 by drawing them through the tufted feet. 



At fig. B is shown the common FISH-LOUSE, which is parasitic upon many species of 

 fish, clinging tightly by means of their hooked legs. It is thought by many fishermen 

 that the creature is by no means hurtful to the fish, but that it is absolutely beneficial, 

 causing death if removed. 



A RATHER curious and tolerably plentiful species of Isopod crustacean is seen at 

 figs. C and D. This is the SHRIMP-FIXER, so called from its habit of affixing itself to shrimps 

 and prawns, concealing itself under the side of the carapace. Any number of these curious 

 parasites may be obtained from a fishmonger's shop, by the simple process of looking over 

 his stock of prawns, and picking out those which have a swelling at the side of the 

 carapace. The fishermen, who have the oddest ideas about marine objects, and know as 

 little about shrimps as a ploughman about worms, generally fancy that these parasites are 

 young soles ! probably on account of the general shape of the male. 



Fig. C represents the female of this crustacean much magnified, and showing the 

 under side, for the purpose of exhibiting the mass of eggs which are congregated beneath 

 the body, and kept in their places by the pouch formed by the plates attached to the legs. 

 Owing to the pressure caused by the carapace of the prawn, the sides of the Shrimp- 

 fixer are dissimilar, and distorted individuals, like that of the figure, are very common, 



In all the members of this genus the male is much smaller than the female, being 

 barely one-sixth the size of his mate, and is narrow and elongated, whereas she is wide, 

 pear-shaped, and ending in a point. The false legs are ten in number, five on each side, 

 and modified into triangular membranous plates, forming a pouch for the reception of 

 the eggs. 



The colour of this species is greenish, with a slight lustre above, and dark at the edges 

 of the plates. 



THE members of the genus lone may be known by the appendages of the abdomen, 

 which are thread-like and arranged round the body. Figs. E and F represent the two 

 sexes of these curious crustaceans, the larger being the female. Both, however, are 

 magnified, and the male is of minute dimensions when compared with the other sex. 



This creature is also a parasite like the preceding, but makes its home within the 

 thoracic plate of the burrowing crab ( Callianassa subterranea), which has already been 

 described on page 612. It forms a tumour on the side, and can be removed in a living 

 state. It seems that both sexes are to be found under the same shell, the tiny male 

 holding firmly to the appendages of his mate like a little child holding to its mother's 

 dress. The colour of this species is orange-yellow, and the appendages are white. 



Mr. Tuffen West has favoured me with the following remarks upon an allied 

 crustacean : " Some years ago, I assisted in the dissection and made drawings of the male 

 and female of a remarkable crustacean taken from the gills of a hermit-crab. It was 

 thought that a new genus would have to be constituted for it. In the female of this 

 species there was a distinct space left between the plates covering the ova, for the 

 accommodation of the male, and it is thought doubtful whether he ever takes any food. 

 The males are model husbands : having once selected a mate, they never leave her." 



Fig. A on the next illustration represents another wood-boring crustacean, called the 

 TIMBER-BORING SHRIMP, or GRIBBLE. 



Though belonging to another family, this creature is as destructive as that which has 

 already been described, but makes its tunnels in a different manner, burrowing deeply 



