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Part III — Twenty-third Annual Report 



motion of the water which would tend to float it away. It clings with 

 all its pereiopods to the silk cloth of the bottom until the wave motion 

 ceases, when it starts crawling again. Immediately the box is agitated, 

 again it halts and holds on. 



In its ability to notice particles of food, the megalops appears to be as 

 keen-sighted as the zoea. Mead contrasts the habits of the zoea and 

 megalops. 



The next, that is the first young stage, swims about after copepods, and 

 is to be seen swimming forward with the two chelae extended together 

 straight in front. The antennae of this stage are longer than in the 

 megalops, and the following stage has still longer antennae 



The stages subsequent to the megalops are even more difficult to 

 dislodge from the corner of the box. They cling tenaciously to the 

 bottom (silk gauze) until the water is withdrawn and they are left 

 stranded. Then they loose their hold to follow up the water. This fact 

 probably accounts for these stages never being met with in the tow-net. 

 They are really bottom forms, and in shallow water would require to be 

 able to stick well to stones or in crevices to prevent their being washed 

 away. 



A young form will sometimes swim round the edge of the box with the 

 off antenna stretched out in front and the near one thrown back along 

 the body. 



Appellof remarks regarding the first young stage that they hide in dark 

 corners or under stones. They are then very stationary. He draws 

 attention to the great caution shown by the young lobster, and considers 

 that, in consequence of that trait, a relatively large percentage of them 

 should survive. 



On the approach of winter the little lobsters in the Laboratory became 

 very sluggish. In November and December 1902 they were rarely seen, 

 except when the boxes were lifted. They stuck to the darkest corner of 

 the box, and did not move about so much as they did earlier in the year. 

 During these months there were hardly any copepods in the water supply, 

 and this may have had something to do with their sluggishness. The 

 increasing cold was, however, doubtless the main predisposing cause of 

 their inactivity. 



One of the most noticeable features that accompanies the transition from 

 the zoea to the megalops is the sudden change in the character of the 

 animal. The zoea swims about in an aimless way, except for the 

 moments when it pursues a copepod. It paddles persistently, and when 

 it strikes against the side of the box it jerks away quickly. It is not 

 disturbed by noticing anything ; all it appears to see is the little particles 

 of food. It evidently sees short distances only. The main point is its 

 indifference to possible danger ; it does not attempt in any way to conceal 

 itself. In the zoea stage the lobster had no fear or premonition ; in the 

 megalops, it assumes with the adult garb the haunting fear of attack, 

 which leads it to hide itself in some protecting crevice. It comes to 

 rest in the darkest corner of the box, and while swimming about is 

 always on the alert for a possible foe. For everything, food and pro- 

 tection, it has to be completely self-dependent. The desire to hide 

 appeared with the necessity. The bottom life is, without doubt, a 

 dangerous one, possibly more so than the pelagic existence it had just 

 passed through. Its eye still enables it to pick up copepods ; it is large, 

 as in all the early stages of decopod Crustacea. It no longer swims 

 aimlessly about, but simply occasionally on a foraging expedition. 



All the larvae ate crab's liver, and hunt it by sight as it falls. And in 

 the case of the megalops, when a little crabs' liver was introduced into the 

 box, the lobster became very excited and rushed hither and thither, 



