Robert Caruana is quite correct when he writes that the plant Lychnis Chalcedonica has nothing to do with the plant that used to grow in fort St Angelo known as Tribulus Terrestris (Maltese Cross Flower, July 20).

This plant is known by a multitude of names like puncture vine, caltrop, yellow vine, goathead, bindy eye, bullhead, burnut, burra gokhroo, cat's head, common dubbeltjie, devil's thorn, devil's weed, Maltese Cross, Mexican sandbur among others. I remember seeing this plant growing in St Angelo in the mid-1970s. Contrary to the claim that it flourished only in the for, this plant is widespread throughout the globe and is found in Southern Europe, Southern Asia, Africa, the United States and Australia.

Interestingly enough nowadays it is being promoted as an aphrodisiac and testosterone booster besides having muscle building properties.