ANTHOZOA OF THE WOODS HOLE REGION. 24I 



Habitat: The species has been found by me only in burrows on sandy and pebbly beaches usually 

 just about or slightly below low-tide line, and always attached to a smooth cobblestone. In the aquarium 

 it will adhere to almost any smooth support, or even the sides or bottom of the dish or aquarium. 



Distribution: The species is accounted rather rare. This may be due in part to the burrowing 

 habit and to the close simulation in color of the tentacles and oral disk as they appear at the mouth of 

 the burrow, rendering difficult its detection unless one looks for it with some care. But I have not 

 found it in any such numbers as to suggest it as a common or abundant species. Verrill reports its 

 distribution from Long Island Sound to Vineyard Sound. I have also taken it in Buzzards Bay adjacent 

 to Woods Hole. 



Sagartia lucise Verrill. [PI. xli, fig. i and 2.] 



Sagartia luciie Verrill, Am. Jour. Sci.. 4th, vol. vi, 1898. p. 493. Parker, Am. Nat. .vol. xx-^av, 1900; ibid., vol. xxxvi, 

 1902, p. 491. Davenport, Mark Mem. Vol. 



This beautiful little actinian, formerly a stranger to the faima of Woods Hole, is now one of the most 

 abundant of tlie littoral species, occurring almost everywhere — on rocks, eelgrass, fucus, shells, piles, 

 etc. It is a small species, varj'ing from 10 to 18 mm. in height, by about 4 to 6 mm. in diameter. The 

 body is smootli and highly contractile, dull olive greenish in color, with a variable number of vertical 

 yellowish or orange stripes. Tentacles rather numerous, from 25 to 50, in several illy defined whorls, 

 long and delicate, and very contractile, pale greenish, sometimes tinged with whitish. Oral disk vari- 

 able as to shape and color; usually flat or concave, greenish, or sometimes with darker radial lines, and 

 often with conspicuous bars at base of directive tentacles. It will more often be obsei-ved that only a 

 single bar is present. This is due to the fact that a common mode of fission, to be mentioned later, often 

 leaves but one of these bars apparent. Acontia freely extruded tlirough body or mouth. 



Reproduction: At certain times sexual propagation is active, and in his original description Verrill 

 States that young embryos might be seen swimming in the cavity of the translucent tentacles. One 

 may also find at certain times in sections of the animal the inclusion in the mesenteries of genital cells. 

 So far as my own observation has gone, however, another mode seems to be of more general occurrence — 

 an asexual one, namely, fission. I have repeatedly observed this process in all stages at almost any 

 time during midsummer. It is not difficult, indeed, to observe the process from its inception to com- 

 pletion, for it goes forward with surprising rapidity, the entire operation occupying from two to three 

 hours, probably often less time. This is most easily studied in small aquaria, or even finger bowls or 

 other glass dishes capable of holding a pint or a liter of water. 



Unlike the process which has been described for Metridium and a few other species, in which fission 

 begins at the mouth or oral disk and proceeds vertically downward, in S. ItuicB the very opposite direction 

 is the one invariably followed, at least so far as I have observed. The first evidence of such fission may 

 be noted in an extension of the pedal disk in a plane parallel with the oral axis. If this extension is to 

 initiate the process of fission there will soon be distinguishable the appearance of a constriction of this 

 elongated disk and the organization of a sort of double foot, in which may be seen the radial arrangements 

 of the proximal ends of the mesenteries. The stretching of the disk is followed by a corresponding con- 

 dition of the walls of the column, a condition which will soon be seen to involve the entire body and oral 

 disk. Careful observation will show a gradual thinning of the basal disk as the stretching goes on more 

 and more, and sooner or later the actual rupture of the bottom of the disk, a rent appearing and passing 

 in a direction at right angles to the oral axis. When this is clearly underway the pulling of the opposite 

 halves of the body continues with increased vigor, and the rent may be followed in an upward and ver- 

 tical direction, which enables tlie observer to actually see the inner organs, mesenteries, acontia, etc. 

 A most curious phenomenon may be seen occasionally as the process continues, namely, as the pulling 

 and consequent tearing proceeds there will occasionally be witnessed the explosion and shooting out of 

 acontia, apparently in response to the physical stimulus involved in the rending of the tissues. It is as 

 if at certain times the pulling was too vigorous and the consequent "hurt" more than the creature could 

 stand with equanimity, and the extrusion of the acontia the expression of protest on the part of the 



