AGASSIZ AND WOODWORTH : VARIATIONS IN EUCOPE. 131 

 The formula for the third stage, with 48 tentacles, is, 



Ac; ^2} tu ^11 J^0> ^2) ^H ^2> ^ 0> ^2> ^\t *2) ^ c» 



or, as in the table, 3, 3, 3 ; 3, 3, 3 ; 3, 3, 3 ; 3, 3, 3 ; of which fourteen 

 specimens were found from the number tabulated for variations. 

 In the fourth stage the formula is, 



Ac> 's» ^2i ^3) ^1} '3' '2j *3i -Lo' ^3j ^2> *3i *U Hi Hi '35 ^ 0) Hi Hi *3) *li 'si Hi *3J ^ ci 



or 96 marginal tentacles. 



Of this normal stage only two specimens were observed. 



Of the fifth stage, with 192 marginal tentacles, of which the follow- 

 ing is the formula, not a single normal stage was observed : 



ic) ^4> hi ^ii ^2) ^4) ^3t ^4> ^15 ^4» ^3j ^45 ^2i *ii *Zi *4i -^ Q' ^4) Hi *4l Hi Hi '35 '45 hi 

 ^4? ^3) ^4' ^25 Hi ^3) ^4) 1^0) ^45 ^3) ^41 ^2? ^45 ^3) '4) '2j '45 '3> ^45 'I5 '4? '35 '4) '2j 

 ^4) ^3» ^4' ' c- 



But a few specimens were seen with the normal number of 15 tentacles 

 in some of the primary divisions of one quadrant. 



Of the sixth stage, with 41 tentacles in each of the primary divisions 

 of the quadrant, not a single specimen was collected. 



It is interesting to note that in the specimens which may be said to 

 belong to the second stage, some of the primary divisions of the quad- 

 rants remain in the first stage with only one tentacle, and others with 

 two, the third tentacle not having developed. 



Between the second and third stage, in a number of specimens, the 

 greatest number of tentacles in a primary division of the quadrant is 

 four, and the smallest one. In a number of cases two or even three of 

 the quadrants remain in the second stage, and only in one quadrant do 

 we find four tentacles in a primary quadrantic division. Similarly, we 

 find a number of specimens with five tentacles as the largest number in 

 any primary quadrantic division, and some of the quadrants in the second 

 stage, but none in the first. Even when we come to six tentacles as the 

 largest number of tentacles in any primary quadrantic division, we still find 

 some of the primary quadrantic divisions in the second stage, and occa- 

 sionally a whole quadrant or a quadrantic division above the first stage, 

 as is the case in the second stage and stages intermediate with the third. 



Only four specimens typical of the normal third stage w^ere observed, 

 and the great majority of the other specimens in which seven tentacles 

 were found in a quadrantic division belonged to stages approximating 

 the third more nearly than the second. Only a small proportion of the 

 specimens were observed in which the quadrantic divisions belonged to 



