THE AMERICAN LOBSTER. 179 



DESCRIPTION OF SMALL LOBSTERS. 



The number of molts or the rapidity of growth is a question which now assumes 

 special interest and, as I shall eventually show, it is subject to considerable individual 

 variation. 



Two young lobsters alter the seventh molt measured 18.4 and 19.5 mm. (Nos. 1, 2, 

 table 3")) and remained in this stage 21 and 18 days respectively. 



Lobster No. 1 (table 35). — The first of these was raised from the fourth stage. Its 

 color in the sixth stage is represented on plate 24. The animal after the seventh molt 

 was light brown, tinged with green, when observed on August 20. It exhibited the 

 "death-feigning habit" in a very marked degree. This lobster molted for the eighth 

 time on September 10, and died the day following, when it measured 21.2 mm. It was 

 hatched about May 27, and was therefore 107 days old. 



Lobster No. 2 (table 35). — This young female lobster had just molted when first 

 examined on July 13, and was theu without doubt in the sixth stage. In color it 

 closely resembled fig. 37, plate 24. It molted for the seventh time on July 27, when it 

 attained a length of 19.5 mm. The color at this time was but little changed, being 

 a deep chocolate above, with the tendon marks on the carapace equally prominent. 



The triangular rostrum is somewhat uarrower. The " finger " of the large claw 

 aud the outer branch of the tail-fan are cream-colored. The latter, as in the sixth 

 stage, carries a very long fringe of seta3, which becomes characteristic of the adolescent 

 period. These setae are about two-thirds the length of the uropod. The left cheliped, 

 which was thrown off at the time of the sixth molt, had grown out again, so that after 

 the seventh ecdysis the length of the new appendage was about seven-tenths of that 

 on the opposite side. The length of the right chela was 6.5 mm.; of the left, 4.5 mm. 



The stalked eyes are now very large aud continue to grow relatively faster than 

 the rest of the body until they attain great prominence in the adolescent stages, as 

 already described. 



The first pair of abdominal appendages are present as small buds, aud after the 

 next molt their size is not greatly increased. 



After the eighth molt (August 14, length 22.G mm.) there was but little noticeable 

 chauge in color. The general cast is still brown, with a bluish -green tinge on the 

 carapace. The length of the fringing set* of tail fan — 1£ mm. — nearly equals that of 

 the telson. The median sternal spines are present on the second to fifth abdominal 

 somites, and have a bluish color. 



Lobster No. 3 (table 35). — This young female lobster was raised from the egg and 

 placed under observation when in the third stage, July 4, 1892. At this time it was 

 11 mm. long. It molted to the sixth stage on August 13, and when I finally left Woods 

 Hole on the 23d of this month there had been no noteworthy change. When examined 

 on September 22, by Dr. E. A. Andrews, it had attained the length of 19.75 mm. It is 

 therefore highly probable that only one intervening molt had occurred and that this 

 happened late in August or early in the following month. It died before another 

 ecdysis, on the 5th of October, when it was about 105 days old, having molted eight 

 times. 



Lobster No. 4 (table 35). — When this lobster came under systematic observation, 

 on the 25th of July, it was iu the sixth stage and 10.3 mm long. An account of its 

 ecdyses, which were carefully watched, one occurring on that very day while in a dish 

 upon my table, will be given in another place. (See p. 183.) 



