[History of microscopy in Spain]. / Apuntes sobre la historia de la microscopía en España.

Nowadays, many Spanish research centers have excellent electronic microscopy services. The current situation, however, should not allow us to forget that the initial steps of microscopy in Spain were very difficult. The construction of excellent optical microscopies in the late XIX century, and their almost immediate introduction in Spain, coincides with a period of thriving scientific activity in our country. Both micrography and histology saw the highlights of their development in Spain, with scientists such as Ramón y Cajal, Río Hortega, Ferrán, Simarro, among others, all of them widely known at present. This article evokes briefly the vicissitudes of Spanish microscopy, from its very beginning in 1843, when the Allgemeine Anatomie by Jacob Henle was translated into Spanish, to present. Scientific historical facts in this article are often accompanied with anecdotes, which show the human aspect of those great scientists. The persevering task carried out by researchers whose names have been recorded in the history of Spanish science and technology, have established the grounds in which our current development is based.

Redescription of Phacodinium metchnikoffi (Ciliophora, Hypotrichida): general morphology and taxonomic position.

Living and stained specimens of Phacodinium metchnikoffi, collected near Madrid, Spain, were studied under light microscopy. Infraciliature was stained using a silver-impregnation procedure. The somatic infraciliature is composed of a relatively small number of discontinuous kinetics, formed by groups of few kinetosomes (pallets). The buccal ciliature is composed of an adoral zone of membranelles and a paroral formation otherwise unknown in ciliates, with many short kineties, which lie on a rigid stem. We propose that P. metchnikoffi is a primitive hypotrich and, consequently, we present a new classification system for hypotrichs.

Description of two species of nassophorean ("Hypostome") ciliates, Nassulopsis elegans (Ehrenberg, 1833) and Zosterodasys derouxi n.sp., with comments on their systematic and phylogenetic affinities.

Most of the so-called "lower hypostomes", nassophorean ciliates in the most recent classifications of the phylum Ciliophora, have been little studied in modern times (e.g., employing methods of silver impregnation, a technique widely considered indispensable in comparative taxonomic work on these protists today). In this paper, we present descriptions of two species, a new strain of Nassulopsis elegans (Ehr., 1833) and Zosterodasys derouxi n.sp., based primarily on use of the pyridinated silver carbonate method of Fernández-Galiano. From our own data, especially on the oral hypostomial frange of the first organism and the true somatic synhymenium of the second, and review of the relevant literature, we suggest that the phylogenetic affinities of these forms need to be reassessed. We also tentatively propose some changes in the suprafamilial classification of the ciliate groups involved. While recognizing the need for additional information that can be supplied only by future ultrastructural studies and comparative morphogenetic investigations, we briefly offer the following two speculative ideas at this time: (1) that Nassulopsis be removed from the order Synhymeniida and be considered an evolutionarily primitive genus of the "higher" order Nassulida; and (2) that Zosterodasys be considered a "pivotal" primitive nassophorean that may have given rise, phylogenetically, not only to the more evolved groups of its own class (the Nassophorea) but also to the (primitive groups of the) entire neighboring class Phyllopharyngea.

Cortical morphogenesis and conjugation process in Caenomorpha medusula (Ciliophora, Heterotrichida).

The new oral infraciliature comes from the posterior longitudinal proliferation of numerous somatic kineties of the parental perizonal zone during the bipartition of Caenomorpha medusula. The new perizonal zone of the opisthe originates from proliferation of the anterior extremes of all the somatic kineties that make up the parental perizonal zone. The proter retains both, the oral infraciliature and the perizonal zone of the parental cell. Conjugation in C. medusula presents three maturation divisions and three postzygotic divisions. During conjugation the oral infraciliature of each conjugant degenerates to be replaced by a new one.