INK AMERICAN LOBSTER, 177 



that the dactyl is bent upward as much as forty degrees away from the propodus, so 

 that the cutting edges meet but imperfectly. 



Larva No. 36, table 34, was nearly ready to molt to the fifth stage on July 17. It 

 was of an opaque greenish-brown color, the claws deep brown. The carapace had a 

 dull, bluish luster when strong light was reflected from it, a well-recognized mark of 

 the molting state. 



Two days later it was in the fifth stage. The carapace and upper surfaces of the 

 abdomen were now greenish brown. The white tendon mark on the side of the cara- 

 pace below the cervical groove was very prominent. The light areas on the first 

 abdominal ring and upon the uropods were rather faint, and the chelae, as usual, were 

 tipped with cream color. 



The remarkable "death-feigning habit," which I shall discuss later, was developed 

 in this larva to an unusual degree. A colored drawing of this lobster after the sixth 

 molt, which occurred about July 30, is represented in plate 25. 



The fifth larval stage lasted in five observed cases from 11 to 18 days. 



THE SIXTH STAGE. 



The average length of five lobsters known to have molted six times was 16 mm., 

 the extremes being 15 and 17 mm. 



I have already referred to the color of this stage, which is represented in an indi- 

 vidual raised from the egg on plate 25. The general cast of color of the upper parts 

 is often dark green or greenish-brown, and the "tendon-marks" on the carapace have 

 now become very conspicuous. Equally characteristic are the snow white pleura of 

 the first abdominal ring. 



A dorsal view of another lobster of this stage is given on plate 24. The coloring 

 is from the sixth stage of larva No. 3, table 34. The whole animal is of a reddish- 

 chocolate color, against which the white spots contrast very sharply. In the cervical 

 groove there is a narrow transverse white area, a large white spot on the distal 

 extremity of the meros of the cheliped, in addition to those already mentioned and 

 the flattened rostrum is conspicuous for its absence of color, being but faintly tinged 

 with green. 



A young lobster captured with the tow net in Woods Hole Harbor in the day- 

 time, August 23, 1890, resembles the sixth stage, already described. The length of 

 the lobster was 10.5 mm. (For record of the capture of other lobsters in sixth stage, 

 see table on p. 187.) 



The individual color-changes which these lobsters undergo were well illustrated in 

 a specimen, 16 mm. long, captured in the net July 24, 1890. When first taken it was 

 bright bluish-green, excepting a slight amount of brownish pigment visible on some 

 of the appendages. This lobster was accidentally left over night in a glass dish of 

 water on my work-table. In the morning it had a decided reddish-brown color and 

 was very weak. One is reminded of the similar but more striking change in color 

 which the remarkable little lizard Anolis princeps, of the Southern States, undergoes 

 when it is suddenly stimulated. 



Larva? have also been captured in the tow, from 15 to 16 mm. long, which resembled 

 more nearly the fourth stage in color, but undoubtedly belonged to the fifth and sixth 

 stages. 



F. C. B. 1895—12 



