jambu-plaksa-salmali-kusa-kraunca-saka-puskara-samjnas tesam parimanam purvasmat purvasmad uttara uttaro yatha-sankhyam dvi-guna-manena bahih samantata upaklptah.
jambu—Jambu; plaksa—Plaksa; salmali—Salmali; kusa—Kusa; kraunca—Kraunca; saka—Saka; puskara—Puskara; samjnah—known as; tesam—of them; parimanam—measurement; purvasmat purvasmat—from the former; uttarah uttarah—the following; yatha—according to; sankhyam—number; dvi-guna—twice as much; manena—with a measure; bahih—outside; samantatah—all around; upaklptah—produced.
The names of the islands are Jambu, Plaksa, Salmali, Kusa, Kraunca, Saka and Puskara. Each island is twice as large as the one preceding it, and each is surrounded by a liquid substance, beyond which is the next island.
The ocean in each planetary system has a different type of liquid. How they are situated is explained in the next verse.
Link to this page: https://prabhupadabooks.com/sb/5/1/32