SUMMARY 365 



Information is required on the following points. 



(1) Where is the animal most commonly met with? 



(2) Does it occur at sea in vast shoals or isolated or both, and under what meteorological conditions? 



(3) Physalia occurs in two forms, right- and left-handed: are both forms equally common and do they 

 occur together? 



(4) Is it difficult for an observer on shipboard who is familiar with boat-sailing to distinguish the 

 right- from the left-hander by the way it is orientated to the wind? (The right-hander appears to be 

 hove-to on the port-tack and drifts to the left of the down-wind direction, and vice versa, the tentacles 

 acting as a drogue.) 



(5) Fixes are required for animals definitely observed to be right- or left-handers with a record of 

 wind-force. 



(6) In a wind does the animal drift along steadily? In a sudden lull does it fall over into the wind? 

 Subsequently, and in a flat calm, does the animal roll about and somersault to right itself? 



(7) Is Physalia ever observed in long parallel wind-rows? 



(8) Records of recollection of previous observations on Physalia in any oceans are needed. 



(9) Precise records are needed of the effects of stinging by Physalia (identified as having a bladder that 

 rests on the surface). 



SUMMARY 



1. There is only one species of Portuguese man-of-war, Physalia physalis (L.), though it occurs 

 everywhere in two forms, the so-called right-handed and left-handed. Both forms were found together 

 in the Canary Islands. The question of right- and left-handedness is discussed. 



2. Observations from a boat were made at close quarters on left-handed specimens drifting in a 

 moderate breeze at slack tide. The angle of drift from down-wind direction was measured, and the 

 rate of drift determined. 



3. The well-known somersaulting phenomena were studied in open water. They were seen 

 generally in a calm and followed loss of equilibrium in the absence of a breeze. 



4. Specimens ranging in float-length from 11 to 180 mm. were anaesthetized and fixed for 

 morphological study. 



5 . The animal is shown to consist of a hypertrophied asexual larva acting as nurse-carrier for other 

 larvae, the polyps, and adults, the medusoid gonophores. 



6. The pattern of budding has been determined. There are two budding-zones on the under and 

 windward side of the oral half of the float, separated by a gap into a main zone and a reduced oral zone. 

 The budding system is basically the same in both. 



7. The single cormidia of a number of specimens, both young and old, have been compared with 

 one another on the same specimen and from specimen to specimen, and photographic records made 

 from several angles. 



8. The general pattern of budding in a single cormidium shows a series of about a dozen tripartite 

 groups, consisting each of a single gastrozooid and its associated tentacle and nematocyst nursery (the 

 ampulla) together with a complex gonodendron, each group budded from the base of its predecessor 

 with the youngest group formed at the aboral end. Secondary branches and branchlets carrying still 

 more series of tripartite groups are produced from the bases of certain groups of the first series, and 

 tertiary ones from the bases of some groups of the secondary series. A well-marked series of these 

 branches is formed to leeward of the main series. 



9. Full details of sexual reproduction are unknown and ripe ova have never been observed. 

 Physalia is dioecious. Some of the so-called ' male ' gonophores are female. 



10. There is no evidence that the so-called 'female' medusoids are shed and that the jelly-polyps 

 (Gallertpolypoide) represent their stalks, as has been suggested. The ' female ' medusoids are necto- 

 phores, not concerned with sexual reproduction. 



